Esempio n. 1
0
class Plot_tau_g(QWidget):
    """
    Widget for plotting the group delay
    """
    # incoming, connected in sender widget (locally connected to self.process_signals() )
    sig_rx = pyqtSignal(object)

    #    sig_tx = pyqtSignal(object) # outgoing from process_signals

    def __init__(self):
        super().__init__()
        self.verbose = False  # suppress warnings
        self.algorithm = "auto"
        self.needs_calc = True  # flag whether plot needs to be recalculated
        self.tool_tip = self.tr("Group delay")
        self.tab_label = "\U0001D70F(f)"  # "tau_g" \u03C4

        self.cmb_algorithm_items =\
            ["<span>Select algorithm for calculating the group delay.</span>",
             ("auto", "Auto", "<span>Try to find best-suited algorithm.</span>"),
             ("scipy", "Scipy", "<span>Scipy algorithm.</span>"),
             ("jos", "JOS", "<span>J.O. Smith's algorithm.</span>"),
             ("shpak", "Shpak", "<span>Shpak's algorithm for SOS and other IIR"
              "filters.</span>"),
             ("diff", "Diff", "<span>Textbook-style, differentiate the phase."
              "</span>")
             ]

        self._construct_UI()

    def _construct_UI(self):
        """
        Intitialize the widget, consisting of:
        - Matplotlib widget with NavigationToolbar
        - Frame with control elements
        """
        self.chkWarnings = QCheckBox(self.tr("Verbose"), self)
        self.chkWarnings.setChecked(self.verbose)
        self.chkWarnings.setToolTip(
            self.
            tr("<span>Print messages about singular group delay and calculation times."
               "</span>"))

        self.cmbAlgorithm = QComboBox(self)
        qcmb_box_populate(self.cmbAlgorithm, self.cmb_algorithm_items,
                          self.algorithm)

        layHControls = QHBoxLayout()
        layHControls.addStretch(10)
        layHControls.addWidget(self.chkWarnings)
        # layHControls.addWidget(self.chkScipy)
        layHControls.addWidget(self.cmbAlgorithm)

        # This widget encompasses all control subwidgets:
        self.frmControls = QFrame(self)
        self.frmControls.setObjectName("frmControls")
        self.frmControls.setLayout(layHControls)

        self.mplwidget = MplWidget(self)
        self.mplwidget.layVMainMpl.addWidget(self.frmControls)
        self.mplwidget.layVMainMpl.setContentsMargins(*params['mpl_margins'])
        self.mplwidget.mplToolbar.a_he.setEnabled(True)
        self.mplwidget.mplToolbar.a_he.info = "manual/plot_tau_g.html"
        self.setLayout(self.mplwidget.layVMainMpl)

        self.init_axes()
        self.draw()  # initial drawing of tau_g

        # ----------------------------------------------------------------------
        # GLOBAL SIGNALS & SLOTs
        # ----------------------------------------------------------------------
        self.sig_rx.connect(self.process_sig_rx)
        # ----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        # ----------------------------------------------------------------------
        self.mplwidget.mplToolbar.sig_tx.connect(self.process_sig_rx)
        self.cmbAlgorithm.currentIndexChanged.connect(self.draw)

# ------------------------------------------------------------------------------

    def process_sig_rx(self, dict_sig=None):
        """
        Process signals coming from the navigation toolbar and from sig_rx
        """
        # logger.debug("Processing {0} | needs_calc = {1}, visible = {2}"
        #              .format(dict_sig, self.needs_calc, self.isVisible()))
        if self.isVisible():
            if 'data_changed' in dict_sig or 'home' in dict_sig or self.needs_calc:
                self.draw()
                self.needs_calc = False
            elif 'view_changed' in dict_sig:
                self.update_view()
        else:
            if 'data_changed' in dict_sig or 'view_changed' in dict_sig:
                self.needs_calc = True

# ------------------------------------------------------------------------------

    def init_axes(self):
        """
        Initialize the axes and set some stuff that is not cleared by
        `ax.clear()` later on.
        """
        self.ax = self.mplwidget.fig.subplots()
        self.ax.xaxis.tick_bottom()  # remove axis ticks on top
        self.ax.yaxis.tick_left()  # remove axis ticks right

# ------------------------------------------------------------------------------

    def calc_tau_g(self):
        """
        (Re-)Calculate the complex frequency response H(f)
        """
        bb = fb.fil[0]['ba'][0]
        aa = fb.fil[0]['ba'][1]

        # calculate H_cmplx(W) (complex) for W = 0 ... 2 pi:
        # scipy: self.W, self.tau_g = group_delay((bb, aa), w=params['N_FFT'],
        #                                           whole = True)

        if fb.fil[0]['creator'][0] == 'sos':  # one of 'sos', 'zpk', 'ba'
            self.W, self.tau_g = group_delay(
                fb.fil[0]['sos'],
                nfft=params['N_FFT'],
                sos=True,
                whole=True,
                verbose=self.chkWarnings.isChecked(),
                alg=self.cmbAlgorithm.currentData())
        else:
            self.W, self.tau_g = group_delay(
                bb,
                aa,
                nfft=params['N_FFT'],
                whole=True,
                verbose=self.chkWarnings.isChecked(),
                alg=self.cmbAlgorithm.currentData())
            #                                   self.chkWarnings.isChecked())

        # Zero phase filters have no group delay (Causal+AntiCausal)
        if 'baA' in fb.fil[0]:
            self.tau_g = np.zeros(self.tau_g.size)

# ------------------------------------------------------------------------------

    def draw(self):
        self.calc_tau_g()
        self.update_view()

# ------------------------------------------------------------------------------

    def update_view(self):
        """
        Draw the figure with new limits, scale etc without recalculating H(f)
        """
        # ========= select frequency range to be displayed =====================
        # === shift, scale and select: W -> F, H_cplx -> H_c
        f_max_2 = fb.fil[0]['f_max'] / 2.
        F = self.W * f_max_2 / np.pi

        if fb.fil[0]['freqSpecsRangeType'] == 'sym':
            # shift tau_g and F by f_S/2
            tau_g = np.fft.fftshift(self.tau_g)
            F -= f_max_2
        elif fb.fil[0]['freqSpecsRangeType'] == 'half':
            # only use the first half of H and F
            tau_g = self.tau_g[0:params['N_FFT'] // 2]
            F = F[0:params['N_FFT'] // 2]
        else:  # fb.fil[0]['freqSpecsRangeType'] == 'whole'
            # use H and F as calculated
            tau_g = self.tau_g

        # ================ Main Plotting Routine =========================
        # ===  clear the axes and (re)draw the plot

        if fb.fil[0]['freq_specs_unit'] in {'f_S', 'f_Ny'}:
            tau_str = r'$ \tau_g(\mathrm{e}^{\mathrm{j} \Omega}) / T_S \; \rightarrow $'
        else:
            tau_str = r'$ \tau_g(\mathrm{e}^{\mathrm{j} \Omega})$'\
                + ' in ' + fb.fil[0]['plt_tUnit'] + r' $ \rightarrow $'
            tau_g = tau_g / fb.fil[0]['f_S']

        # ---------------------------------------------------------
        self.ax.clear()  # need to clear, doesn't overwrite
        line_tau_g, = self.ax.plot(F, tau_g, label="Group Delay")
        # ---------------------------------------------------------

        self.ax.xaxis.set_minor_locator(
            AutoMinorLocator())  # enable minor ticks
        self.ax.yaxis.set_minor_locator(
            AutoMinorLocator())  # enable minor ticks
        self.ax.set_title(r'Group Delay $ \tau_g$')
        self.ax.set_xlabel(fb.fil[0]['plt_fLabel'])
        self.ax.set_ylabel(tau_str)
        # widen y-limits to suppress numerical inaccuracies when tau_g = constant
        self.ax.set_ylim(
            [max(np.nanmin(tau_g) - 0.5, 0),
             np.nanmax(tau_g) + 0.5])
        self.ax.set_xlim(fb.fil[0]['freqSpecsRange'])

        self.redraw()

# ------------------------------------------------------------------------------

    def redraw(self):
        """
        Redraw the canvas when e.g. the canvas size has changed
        """
        self.mplwidget.redraw()
Esempio n. 2
0
class Plot_3D(QWidget):
    """
    Class for various 3D-plots:
    - lin / log line plot of H(f)
    - lin / log surf plot of H(z)
    - optional display of poles / zeros
    """

    # incoming, connected in sender widget (locally connected to self.process_sig_rx() )
    sig_rx = pyqtSignal(object)

    #    sig_tx = pyqtSignal(object) # outgoing from process_signals

    def __init__(self):
        super().__init__()
        self.zmin = 0
        self.zmax = 4
        self.zmin_dB = -80
        self.cmap_default = 'RdYlBu'
        self.data_changed = True  # flag whether data has changed
        self.tool_tip = "3D magnitude response |H(z)|"
        self.tab_label = "3D"

        self._construct_UI()

# ------------------------------------------------------------------------------

    def process_sig_rx(self, dict_sig=None):
        """
        Process signals coming from the navigation toolbar and from ``sig_rx``
        """
        # logger.debug("Processing {0} | data_changed = {1}, visible = {2}"\
        #              .format(dict_sig, self.data_changed, self.isVisible()))
        if self.isVisible():
            if 'data_changed' in dict_sig or 'home' in dict_sig or self.data_changed:
                self.draw()
                self.data_changed = False
        else:
            if 'data_changed' in dict_sig:
                self.data_changed = True

# ------------------------------------------------------------------------------

    def _construct_UI(self):
        self.but_log = PushButton("dB", checked=False)
        self.but_log.setObjectName("but_log")
        self.but_log.setToolTip("Logarithmic scale")

        self.but_plot_in_UC = PushButton("|z| < 1 ", checked=False)
        self.but_plot_in_UC.setObjectName("but_plot_in_UC")
        self.but_plot_in_UC.setToolTip("Only plot H(z) within the unit circle")

        self.lblBottom = QLabel(to_html("Bottom =", frmt='bi'), self)
        self.ledBottom = QLineEdit(self)
        self.ledBottom.setObjectName("ledBottom")
        self.ledBottom.setText(str(self.zmin))
        self.ledBottom.setToolTip("Minimum display value.")
        self.lblBottomdB = QLabel("dB", self)
        self.lblBottomdB.setVisible(self.but_log.isChecked())

        self.lblTop = QLabel(to_html("Top =", frmt='bi'), self)
        self.ledTop = QLineEdit(self)
        self.ledTop.setObjectName("ledTop")
        self.ledTop.setText(str(self.zmax))
        self.ledTop.setToolTip("Maximum display value.")
        self.lblTopdB = QLabel("dB", self)
        self.lblTopdB.setVisible(self.but_log.isChecked())

        self.plt_UC = PushButton("UC", checked=True)
        self.plt_UC.setObjectName("plt_UC")
        self.plt_UC.setToolTip("Plot unit circle")

        self.but_PZ = PushButton("P/Z ", checked=True)
        self.but_PZ.setObjectName("but_PZ")
        self.but_PZ.setToolTip("Plot poles and zeros")

        self.but_Hf = PushButton("H(f) ", checked=True)
        self.but_Hf.setObjectName("but_Hf")
        self.but_Hf.setToolTip("Plot H(f) along the unit circle")

        modes = ['None', 'Mesh', 'Surf', 'Contour']
        self.cmbMode3D = QComboBox(self)
        self.cmbMode3D.addItems(modes)
        self.cmbMode3D.setObjectName("cmbShow3D")
        self.cmbMode3D.setToolTip("Select 3D-plot mode.")
        self.cmbMode3D.setCurrentIndex(0)
        self.cmbMode3D.setSizeAdjustPolicy(QComboBox.AdjustToContents)

        self.but_colormap_r = PushButton("reverse", checked=True)
        self.but_colormap_r.setObjectName("but_colormap_r")
        self.but_colormap_r.setToolTip("reverse colormap")

        self.cmbColormap = QComboBox(self)
        self._init_cmb_colormap(cmap_init=self.cmap_default)
        self.cmbColormap.setToolTip("Select colormap")

        self.but_colbar = PushButton("Colorbar ", checked=False)
        self.but_colbar.setObjectName("chkColBar")
        self.but_colbar.setToolTip("Show colorbar")

        self.but_lighting = PushButton("Lighting", checked=False)
        self.but_lighting.setObjectName("but_lighting")
        self.but_lighting.setToolTip("Enable light source")

        self.lblAlpha = QLabel(to_html("Alpha", frmt='bi'), self)
        self.diaAlpha = QDial(self)
        self.diaAlpha.setRange(0, 10)
        self.diaAlpha.setValue(10)
        self.diaAlpha.setTracking(False)  # produce less events when turning
        self.diaAlpha.setFixedHeight(30)
        self.diaAlpha.setFixedWidth(30)
        self.diaAlpha.setWrapping(False)
        self.diaAlpha.setToolTip(
            "<span>Set transparency for surf and contour plots.</span>")

        self.lblHatch = QLabel(to_html("Stride", frmt='bi'), self)
        self.diaHatch = QDial(self)
        self.diaHatch.setRange(0, 9)
        self.diaHatch.setValue(5)
        self.diaHatch.setTracking(False)  # produce less events when turning
        self.diaHatch.setFixedHeight(30)
        self.diaHatch.setFixedWidth(30)
        self.diaHatch.setWrapping(False)
        self.diaHatch.setToolTip("Set line density for various plots.")

        self.but_contour_2d = PushButton("Contour2D ", checked=False)
        self.but_contour_2d.setObjectName("chkContour2D")
        self.but_contour_2d.setToolTip("Plot 2D-contours at z =0")

        # ----------------------------------------------------------------------
        # LAYOUT for UI widgets
        # ----------------------------------------------------------------------
        layGControls = QGridLayout()
        layGControls.addWidget(self.but_log, 0, 0)
        layGControls.addWidget(self.but_plot_in_UC, 1, 0)
        layGControls.addWidget(self.lblTop, 0, 2)
        layGControls.addWidget(self.ledTop, 0, 4)
        layGControls.addWidget(self.lblTopdB, 0, 5)
        layGControls.addWidget(self.lblBottom, 1, 2)
        layGControls.addWidget(self.ledBottom, 1, 4)
        layGControls.addWidget(self.lblBottomdB, 1, 5)
        layGControls.setColumnStretch(5, 1)

        layGControls.addWidget(self.plt_UC, 0, 6)
        layGControls.addWidget(self.but_Hf, 1, 6)
        layGControls.addWidget(self.but_PZ, 0, 8)

        layGControls.addWidget(self.cmbMode3D, 0, 10)
        layGControls.addWidget(self.but_contour_2d, 1, 10)
        layGControls.addWidget(self.cmbColormap, 0, 12, 1, 1)
        layGControls.addWidget(self.but_colormap_r, 1, 12)

        layGControls.addWidget(self.but_lighting, 0, 14)
        layGControls.addWidget(self.but_colbar, 1, 14)

        layGControls.addWidget(self.lblAlpha, 0, 15)
        layGControls.addWidget(self.diaAlpha, 0, 16)

        layGControls.addWidget(self.lblHatch, 1, 15)
        layGControls.addWidget(self.diaHatch, 1, 16)

        # This widget encompasses all control subwidgets
        self.frmControls = QFrame(self)
        self.frmControls.setObjectName("frmControls")
        self.frmControls.setLayout(layGControls)

        # ----------------------------------------------------------------------
        # mplwidget
        # ----------------------------------------------------------------------
        # This is the plot pane widget, encompassing the other widgets
        self.mplwidget = MplWidget(self)
        self.mplwidget.layVMainMpl.addWidget(self.frmControls)
        self.mplwidget.layVMainMpl.setContentsMargins(*params['mpl_margins'])
        self.mplwidget.mplToolbar.a_he.setEnabled(True)
        self.mplwidget.mplToolbar.a_he.info = "manual/plot_3d.html"
        self.setLayout(self.mplwidget.layVMainMpl)

        self._init_grid()  # initialize grid and do initial plot

        # ----------------------------------------------------------------------
        # GLOBAL SIGNALS & SLOTs
        # ----------------------------------------------------------------------
        self.sig_rx.connect(self.process_sig_rx)
        # ----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        # ----------------------------------------------------------------------
        self.but_log.clicked.connect(self._log_clicked)
        self.ledBottom.editingFinished.connect(self._log_clicked)
        self.ledTop.editingFinished.connect(self._log_clicked)

        self.but_plot_in_UC.clicked.connect(self._init_grid)
        self.plt_UC.clicked.connect(self.draw)
        self.but_Hf.clicked.connect(self.draw)
        self.but_PZ.clicked.connect(self.draw)
        self.cmbMode3D.currentIndexChanged.connect(self.draw)
        self.but_colbar.clicked.connect(self.draw)

        self.cmbColormap.currentIndexChanged.connect(self.draw)
        self.but_colormap_r.clicked.connect(self.draw)

        self.but_lighting.clicked.connect(self.draw)
        self.diaAlpha.valueChanged.connect(self.draw)
        self.diaHatch.valueChanged.connect(self.draw)
        self.but_contour_2d.clicked.connect(self.draw)

        self.mplwidget.mplToolbar.sig_tx.connect(self.process_sig_rx)
        # self.mplwidget.mplToolbar.enable_plot(state = False) # disable initially

# ------------------------------------------------------------------------------

    def _init_cmb_colormap(self, cmap_init):
        """
        Initialize combobox with available colormaps and try to set it to `cmap_init`

        Since matplotlib 3.2 the reversed "*_r" colormaps are no longer contained in
        `cm.datad`. They are now obtained by using the `reversed()` method (much simpler!)

        `cm.datad` doesn't return the "new" colormaps like viridis, instead the
        `colormaps()` method is used.
        """
        self.cmbColormap.addItems(
            [m for m in colormaps() if not m.endswith("_r")])

        idx = self.cmbColormap.findText(cmap_init)
        if idx == -1:
            idx = 0
        self.cmbColormap.setCurrentIndex(idx)

# ------------------------------------------------------------------------------

    def _init_grid(self):
        """ Initialize (x,y,z) coordinate grid + (re)draw plot."""
        phi_UC = np.linspace(0, 2 * pi, 400,
                             endpoint=True)  # angles for unit circle
        self.xy_UC = np.exp(1j * phi_UC)  # x,y coordinates of unity circle

        steps = 100  # number of steps for x, y, r, phi
        # cartesian range limits
        self.xmin = -1.5
        self.xmax = 1.5
        self.ymin = -1.5
        self.ymax = 1.5

        # Polar range limits
        rmin = 0
        rmax = 1

        # Calculate grids for 3D-Plots
        dr = rmax / steps * 2  # grid size for polar range
        dx = (self.xmax - self.xmin) / steps
        dy = (self.ymax - self.ymin) / steps  # grid size cartesian range

        if self.but_plot_in_UC.isChecked():  # Plot circular range in 3D-Plot
            [r,
             phi] = np.meshgrid(np.arange(rmin, rmax, dr),
                                np.linspace(0, 2 * pi, steps, endpoint=True))
            self.x = r * cos(phi)
            self.y = r * sin(phi)
        else:  # cartesian grid
            [self.x, self.y] = np.meshgrid(np.arange(self.xmin, self.xmax, dx),
                                           np.arange(self.ymin, self.ymax, dy))

        self.z = self.x + 1j * self.y  # create coordinate grid for complex plane

        self.draw()  # initial plot

# ------------------------------------------------------------------------------

    def init_axes(self):
        """
        Initialize and clear the axes to get rid of colorbar
        The azimuth / elevation / distance settings of the camera are restored
        after clearing the axes. See
        http://stackoverflow.com/questions/4575588/matplotlib-3d-plot-with-pyqt4-in-qtabwidget-mplwidget
        """

        self._save_axes()

        self.mplwidget.fig.clf()  # needed to get rid of colorbar
        self.ax3d = self.mplwidget.fig.add_subplot(111, projection='3d')
        # self.ax3d = self.mplwidget.fig.subplots(nrows=1, ncols=1, projection='3d')

        self._restore_axes()

# ------------------------------------------------------------------------------

    def _save_axes(self):
        """
        Store x/y/z - limits and camera position
        """

        try:
            self.azim = self.ax3d.azim
            self.elev = self.ax3d.elev
            self.dist = self.ax3d.dist
            self.xlim = self.ax3d.get_xlim3d()
            self.ylim = self.ax3d.get_ylim3d()
            self.zlim = self.ax3d.get_zlim3d()

        except AttributeError:  # not yet initialized, set standard values
            self.azim = -65
            self.elev = 30
            self.dist = 10
            self.xlim = (self.xmin, self.xmax)
            self.ylim = (self.ymin, self.ymax)
            self.zlim = (self.zmin, self.zmax)

# ------------------------------------------------------------------------------

    def _restore_axes(self):
        """
        Restore x/y/z - limits and camera position
        """
        if self.mplwidget.mplToolbar.a_lk.isChecked():
            self.ax3d.set_xlim3d(self.xlim)
            self.ax3d.set_ylim3d(self.ylim)
            self.ax3d.set_zlim3d(self.zlim)
        self.ax3d.azim = self.azim
        self.ax3d.elev = self.elev
        self.ax3d.dist = self.dist

# ------------------------------------------------------------------------------

    def _log_clicked(self):
        """
        Change scale and settings to log / lin when log setting is changed
        Update min / max settings when lineEdits have been edited
        """
        if self.sender().objectName(
        ) == 'but_log':  # clicking but_log triggered the slot
            if self.but_log.isChecked():
                self.ledBottom.setText(str(self.zmin_dB))
                self.zmax_dB = np.round(20 * log10(self.zmax), 2)
                self.ledTop.setText(str(self.zmax_dB))
                self.lblTopdB.setVisible(True)
                self.lblBottomdB.setVisible(True)
            else:
                self.ledBottom.setText(str(self.zmin))
                self.zmax = np.round(10**(self.zmax_dB / 20), 2)
                self.ledTop.setText(str(self.zmax))
                self.lblTopdB.setVisible(False)
                self.lblBottomdB.setVisible(False)

        else:  # finishing a lineEdit field triggered the slot
            if self.but_log.isChecked():
                self.zmin_dB = safe_eval(self.ledBottom.text(),
                                         self.zmin_dB,
                                         return_type='float')
                self.ledBottom.setText(str(self.zmin_dB))
                self.zmax_dB = safe_eval(self.ledTop.text(),
                                         self.zmax_dB,
                                         return_type='float')
                self.ledTop.setText(str(self.zmax_dB))
            else:
                self.zmin = safe_eval(self.ledBottom.text(),
                                      self.zmin,
                                      return_type='float')
                self.ledBottom.setText(str(self.zmin))
                self.zmax = safe_eval(self.ledTop.text(),
                                      self.zmax,
                                      return_type='float')
                self.ledTop.setText(str(self.zmax))

        self.draw()

# ------------------------------------------------------------------------------

    def draw(self):
        """
        Main drawing entry point: perform the actual plot
        """
        self.draw_3d()

# ------------------------------------------------------------------------------

    def draw_3d(self):
        """
        Draw various 3D plots
        """
        self.init_axes()

        bb = fb.fil[0]['ba'][0]
        aa = fb.fil[0]['ba'][1]

        zz = np.array(fb.fil[0]['zpk'][0])
        pp = np.array(fb.fil[0]['zpk'][1])

        wholeF = fb.fil[0]['freqSpecsRangeType'] != 'half'  # not used
        f_S = fb.fil[0]['f_S']
        N_FFT = params['N_FFT']

        alpha = self.diaAlpha.value() / 10.

        cmap = cm.get_cmap(str(self.cmbColormap.currentText()))
        if self.but_colormap_r.isChecked():
            cmap = cmap.reversed()  # use reversed colormap

        # Number of Lines /step size for H(f) stride, mesh, contour3d:
        stride = 10 - self.diaHatch.value()
        NL = 3 * self.diaHatch.value() + 5

        surf_enabled = qget_cmb_box(self.cmbMode3D, data=False) in {'Surf', 'Contour'}\
            or self.but_contour_2d.isChecked()
        self.cmbColormap.setEnabled(surf_enabled)
        self.but_colormap_r.setEnabled(surf_enabled)
        self.but_lighting.setEnabled(surf_enabled)
        self.but_colbar.setEnabled(surf_enabled)
        self.diaAlpha.setEnabled(surf_enabled
                                 or self.but_contour_2d.isChecked())

        # cNorm  = colors.Normalize(vmin=0, vmax=values[-1])
        # scalarMap = cmx.ScalarMappable(norm=cNorm, cmap=jet)

        # -----------------------------------------------------------------------------
        # Calculate H(w) along the upper half of unity circle
        # -----------------------------------------------------------------------------

        [w, H] = sig.freqz(bb, aa, worN=N_FFT, whole=True)
        H = np.nan_to_num(H)  # replace nans and inf by finite numbers

        H_abs = abs(H)
        H_max = max(H_abs)
        H_min = min(H_abs)
        # f = w / (2 * pi) * f_S                  # translate w to absolute frequencies
        # F_min = f[np.argmin(H_abs)]

        plevel_rel = 1.05  # height of plotted pole position relative to zmax
        zlevel_rel = 0.1  # height of plotted zero position relative to zmax

        if self.but_log.isChecked():  # logarithmic scale
            # suppress "divide by zero in log10" warnings
            old_settings_seterr = np.seterr()
            np.seterr(divide='ignore')

            bottom = np.floor(max(self.zmin_dB, 20 * log10(H_min)) / 10) * 10
            top = self.zmax_dB
            top_bottom = top - bottom

            zlevel = bottom - top_bottom * zlevel_rel

            if self.cmbMode3D.currentText(
            ) == 'None':  # "Poleposition": H(f) plot only
                plevel_top = 2 * bottom - zlevel  # height of displayed pole position
                plevel_btm = bottom
            else:
                plevel_top = top + top_bottom * (plevel_rel - 1)
                plevel_btm = top

            np.seterr(**old_settings_seterr)

        else:  # linear scale
            bottom = max(self.zmin, H_min)  # min. display value
            top = self.zmax  # max. display value
            top_bottom = top - bottom
            #   top = zmax_rel * H_max # calculate display top from max. of H(f)

            zlevel = bottom + top_bottom * zlevel_rel  # height of displayed zero position

            if self.cmbMode3D.currentText(
            ) == 'None':  # "Poleposition": H(f) plot only
                #H_max = np.clip(max(H_abs), 0, self.zmax)
                # make height of displayed poles same to zeros
                plevel_top = bottom + top_bottom * zlevel_rel
                plevel_btm = bottom
            else:
                plevel_top = plevel_rel * top
                plevel_btm = top

        # calculate H(jw)| along the unity circle and |H(z)|, each clipped
        # between bottom and top
        H_UC = H_mag(bb,
                     aa,
                     self.xy_UC,
                     top,
                     H_min=bottom,
                     log=self.but_log.isChecked())
        Hmag = H_mag(bb,
                     aa,
                     self.z,
                     top,
                     H_min=bottom,
                     log=self.but_log.isChecked())

        # ===============================================================
        # Plot Unit Circle (UC)
        # ===============================================================
        if self.plt_UC.isChecked():
            #  Plot unit circle and marker at (1,0):
            self.ax3d.plot(self.xy_UC.real,
                           self.xy_UC.imag,
                           ones(len(self.xy_UC)) * bottom,
                           lw=2,
                           color='k')
            self.ax3d.plot([0.97, 1.03], [0, 0], [bottom, bottom],
                           lw=2,
                           color='k')

        # ===============================================================
        # Plot ||H(f)| along unit circle as 3D-lineplot
        # ===============================================================
        if self.but_Hf.isChecked():
            self.ax3d.plot(self.xy_UC.real,
                           self.xy_UC.imag,
                           H_UC,
                           alpha=0.8,
                           lw=4)
            # draw once more as dashed white line to improve visibility
            self.ax3d.plot(self.xy_UC.real, self.xy_UC.imag, H_UC, 'w--', lw=4)

            if stride < 10:  # plot thin vertical line every stride points on the UC
                for k in range(len(self.xy_UC[::stride])):
                    self.ax3d.plot([
                        self.xy_UC.real[::stride][k],
                        self.xy_UC.real[::stride][k]
                    ], [
                        self.xy_UC.imag[::stride][k],
                        self.xy_UC.imag[::stride][k]
                    ], [
                        np.ones(len(self.xy_UC[::stride]))[k] * bottom,
                        H_UC[::stride][k]
                    ],
                                   linewidth=1,
                                   color=(0.5, 0.5, 0.5))

        # ===============================================================
        # Plot Poles and Zeros
        # ===============================================================
        if self.but_PZ.isChecked():

            PN_SIZE = 8  # size of P/N symbols

            # Plot zero markers at |H(z_i)| = zlevel with "stems":
            self.ax3d.plot(zz.real,
                           zz.imag,
                           ones(len(zz)) * zlevel,
                           'o',
                           markersize=PN_SIZE,
                           markeredgecolor='blue',
                           markeredgewidth=2.0,
                           markerfacecolor='none')
            for k in range(len(zz)):  # plot zero "stems"
                self.ax3d.plot([zz[k].real, zz[k].real],
                               [zz[k].imag, zz[k].imag], [bottom, zlevel],
                               linewidth=1,
                               color='b')

            # Plot the poles at |H(z_p)| = plevel with "stems":
            self.ax3d.plot(np.real(pp),
                           np.imag(pp),
                           plevel_top,
                           'x',
                           markersize=PN_SIZE,
                           markeredgewidth=2.0,
                           markeredgecolor='red')
            for k in range(len(pp)):  # plot pole "stems"
                self.ax3d.plot([pp[k].real, pp[k].real],
                               [pp[k].imag, pp[k].imag],
                               [plevel_btm, plevel_top],
                               linewidth=1,
                               color='r')

        # ===============================================================
        # 3D-Plots of |H(z)| clipped between |H(z)| = top
        # ===============================================================

        m_cb = cm.ScalarMappable(
            cmap=cmap)  # normalized proxy object that is mappable
        m_cb.set_array(Hmag)  # for colorbar

        # ---------------------------------------------------------------
        # 3D-mesh plot
        # ---------------------------------------------------------------
        if self.cmbMode3D.currentText() == 'Mesh':
            # fig_mlab = mlab.figure(fgcolor=(0., 0., 0.), bgcolor=(1, 1, 1))
            # self.ax3d.set_zlim(0,2)
            self.ax3d.plot_wireframe(self.x,
                                     self.y,
                                     Hmag,
                                     rstride=5,
                                     cstride=stride,
                                     linewidth=1,
                                     color='gray')

        # ---------------------------------------------------------------
        # 3D-surface plot
        # ---------------------------------------------------------------
        # http://stackoverflow.com/questions/28232879/phong-shading-for-shiny-python-3d-surface-plots
        elif self.cmbMode3D.currentText() == 'Surf':
            if MLAB:
                # Mayavi
                surf = mlab.surf(self.x,
                                 self.y,
                                 H_mag,
                                 colormap='RdYlBu',
                                 warp_scale='auto')
                # Change the visualization parameters.
                surf.actor.property.interpolation = 'phong'
                surf.actor.property.specular = 0.1
                surf.actor.property.specular_power = 5
                #                s = mlab.contour_surf(self.x, self.y, Hmag, contour_z=0)
                mlab.show()

            else:
                if self.but_lighting.isChecked():
                    ls = LightSource(azdeg=0,
                                     altdeg=65)  # Create light source object
                    rgb = ls.shade(
                        Hmag, cmap=cmap)  # Shade data, creating an rgb array
                    cmap_surf = None
                else:
                    rgb = None
                    cmap_surf = cmap

    #            s = self.ax3d.plot_surface(self.x, self.y, Hmag,
    #                    alpha=OPT_3D_ALPHA, rstride=1, cstride=1, cmap=cmap,
    #                    linewidth=0, antialiased=False, shade=True, facecolors = rgb)
    #            s.set_edgecolor('gray')
                s = self.ax3d.plot_surface(self.x,
                                           self.y,
                                           Hmag,
                                           alpha=alpha,
                                           rstride=1,
                                           cstride=1,
                                           linewidth=0,
                                           antialiased=False,
                                           facecolors=rgb,
                                           cmap=cmap_surf,
                                           shade=True)
                s.set_edgecolor(None)
        # ---------------------------------------------------------------
        # 3D-Contour plot
        # ---------------------------------------------------------------
        elif self.cmbMode3D.currentText() == 'Contour':
            s = self.ax3d.contourf3D(self.x,
                                     self.y,
                                     Hmag,
                                     NL,
                                     alpha=alpha,
                                     cmap=cmap)

        # ---------------------------------------------------------------
        # 2D-Contour plot
        # TODO: 2D contour plots do not plot correctly together with 3D plots in
        #       current matplotlib 1.4.3 -> disable them for now
        # TODO: zdir = x / y delivers unexpected results -> rather plot max(H)
        #       along the other axis?
        # TODO: colormap is created depending on the zdir = 'z' contour plot
        #       -> set limits of (all) other plots manually?
        if self.but_contour_2d.isChecked():
            #            self.ax3d.contourf(x, y, Hmag, 20, zdir='x', offset=xmin,
            #                         cmap=cmap, alpha = alpha)#, vmin = bottom)#, vmax = top, vmin = bottom)
            #            self.ax3d.contourf(x, y, Hmag, 20, zdir='y', offset=ymax,
            #                         cmap=cmap, alpha = alpha)#, vmin = bottom)#, vmax = top, vmin = bottom)
            s = self.ax3d.contourf(self.x,
                                   self.y,
                                   Hmag,
                                   NL,
                                   zdir='z',
                                   offset=bottom - (top - bottom) * 0.05,
                                   cmap=cmap,
                                   alpha=alpha)

        # plot colorbar for suitable plot modes
        if self.but_colbar.isChecked() and (
                self.but_contour_2d.isChecked()
                or str(self.cmbMode3D.currentText()) in {'Contour', 'Surf'}):
            self.colb = self.mplwidget.fig.colorbar(m_cb,
                                                    ax=self.ax3d,
                                                    shrink=0.8,
                                                    aspect=20,
                                                    pad=0.02,
                                                    fraction=0.08)

        # ----------------------------------------------------------------------
        # Set view limits and labels
        # ----------------------------------------------------------------------
        if not self.mplwidget.mplToolbar.a_lk.isChecked():
            self.ax3d.set_xlim3d(self.xmin, self.xmax)
            self.ax3d.set_ylim3d(self.ymin, self.ymax)
            self.ax3d.set_zlim3d(bottom, top)
        else:
            self._restore_axes()

        self.ax3d.set_xlabel('Re')  #(fb.fil[0]['plt_fLabel'])
        self.ax3d.set_ylabel(
            'Im'
        )  #(r'$ \tau_g(\mathrm{e}^{\mathrm{j} \Omega}) / T_S \; \rightarrow $')
        #        self.ax3d.set_zlabel(r'$|H(z)|\; \rightarrow $')
        self.ax3d.set_title(
            r'3D-Plot of $|H(\mathrm{e}^{\mathrm{j} \Omega})|$ and $|H(z)|$')

        self.redraw()

# ------------------------------------------------------------------------------

    def redraw(self):
        """
        Redraw the canvas when e.g. the canvas size has changed
        """
        self.mplwidget.redraw()
Esempio n. 3
0
class Plot_Phi(QWidget):
    # incoming, connected in sender widget (locally connected to self.process_sig_rx() )
    sig_rx = pyqtSignal(object)
    # outgoing, distributed via plot_tab_widget
    sig_tx = pyqtSignal(object)

    def __init__(self, parent):
        super(Plot_Phi, self).__init__(parent)
        self.needs_calc = True  # recalculation of filter function necessary
        self.needs_draw = True  # plotting neccessary (e.g. log instead of  lin)
        self.tool_tip = "Phase frequency response"
        self.tab_label = "\u03C6(f)"  # phi(f)
        self._construct_UI()

#------------------------------------------------------------------------------

    def process_sig_rx(self, dict_sig=None):
        """
        Process signals coming from the navigation toolbar and from sig_rx
        """
        logger.debug("Processing {0} | needs_calc = {1}, visible = {2}"\
                     .format(dict_sig, self.needs_calc, self.isVisible()))
        if dict_sig['sender'] == __name__:
            logger.debug("Stopped infinite loop\n{0}".format(
                pprint_log(dict_sig)))
            return

        if self.isVisible():
            if 'data_changed' in dict_sig or 'home' in dict_sig or self.needs_calc:
                self.draw()
                self.needs_calc = False
                self.needs_draw = False
            elif 'view_changed' in dict_sig or self.needs_draw:
                self.update_view()
                self.needs_draw = False
            # elif ('ui_changed' in dict_sig and dict_sig['ui_changed'] == 'resized')\
            #     or self.needs_redraw:
            #     self.redraw()
        else:
            if 'data_changed' in dict_sig:
                self.needs_calc = True
            elif 'view_changed' in dict_sig:
                self.needs_draw = True
            # elif 'ui_changed' in dict_sig and dict_sig['ui_changed'] == 'resized':
            #     self.needs_redraw = True

#------------------------------------------------------------------------------

    def _construct_UI(self):
        """
        Intitialize the widget, consisting of:
        - Matplotlib widget with NavigationToolbar
        - Frame with control elements
        """

        self.cmbUnitsPhi = QComboBox(self)
        units = ["rad", "rad/pi", "deg"]
        scales = [1., 1. / np.pi, 180. / np.pi]
        for unit, scale in zip(units, scales):
            self.cmbUnitsPhi.addItem(unit, scale)
        self.cmbUnitsPhi.setObjectName("cmbUnitsA")
        self.cmbUnitsPhi.setToolTip("Set unit for phase.")
        self.cmbUnitsPhi.setCurrentIndex(0)
        self.cmbUnitsPhi.setSizeAdjustPolicy(QComboBox.AdjustToContents)

        self.chkWrap = QCheckBox("Wrapped Phase", self)
        self.chkWrap.setChecked(False)
        self.chkWrap.setToolTip("Plot phase wrapped to +/- pi")

        layHControls = QHBoxLayout()
        layHControls.addWidget(self.cmbUnitsPhi)
        layHControls.addWidget(self.chkWrap)
        layHControls.addStretch(10)

        #----------------------------------------------------------------------
        #               ### frmControls ###
        #
        # This widget encompasses all control subwidgets
        #----------------------------------------------------------------------
        self.frmControls = QFrame(self)
        self.frmControls.setObjectName("frmControls")
        self.frmControls.setLayout(layHControls)

        #----------------------------------------------------------------------
        #               ### mplwidget ###
        #
        # main widget, encompassing the other widgets
        #----------------------------------------------------------------------
        self.mplwidget = MplWidget(self)
        self.mplwidget.layVMainMpl.addWidget(self.frmControls)
        self.mplwidget.layVMainMpl.setContentsMargins(*params['wdg_margins'])
        self.setLayout(self.mplwidget.layVMainMpl)

        self.init_axes()

        self.draw()  # initial drawing

        #----------------------------------------------------------------------
        # GLOBAL SIGNALS & SLOTs
        #----------------------------------------------------------------------
        self.sig_rx.connect(self.process_sig_rx)

        #----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        #----------------------------------------------------------------------
        self.chkWrap.clicked.connect(self.draw)
        self.cmbUnitsPhi.currentIndexChanged.connect(self.unit_changed)
        self.mplwidget.mplToolbar.sig_tx.connect(self.process_sig_rx)

#------------------------------------------------------------------------------

    def init_axes(self):
        """
        Initialize and clear the axes - this is only called once
        """
        if len(self.mplwidget.fig.get_axes()) == 0:  # empty figure, no axes
            self.ax = self.mplwidget.fig.subplots()
        self.ax.get_xaxis().tick_bottom()  # remove axis ticks on top
        self.ax.get_yaxis().tick_left()  # remove axis ticks right

#------------------------------------------------------------------------------

    def unit_changed(self):
        """
        Unit for phase display has been changed, emit a 'view_changed' signal
        and continue with drawing.
        """
        self.sig_tx.emit({'sender': __name__, 'view_changed': 'plot_phi'})
        self.draw()

#------------------------------------------------------------------------------

    def calc_resp(self):
        """
        (Re-)Calculate the complex frequency response H(f)
        """
        # calculate H_cplx(W) (complex) for W = 0 ... 2 pi:
        self.W, self.H_cmplx = calc_Hcomplex(fb.fil[0],
                                             params['N_FFT'],
                                             wholeF=True)
        # replace nan and inf by finite values, otherwise np.unwrap yields
        # an array full of nans
        self.H_cmplx = np.nan_to_num(self.H_cmplx)

#------------------------------------------------------------------------------

    def draw(self):
        """
        Main entry point:
        Re-calculate \|H(f)\| and draw the figure
        """
        self.calc_resp()
        self.update_view()

#------------------------------------------------------------------------------

    def update_view(self):
        """
        Draw the figure with new limits, scale etc without recalculating H(f)
        """

        self.unitPhi = qget_cmb_box(self.cmbUnitsPhi, data=False)

        f_S2 = fb.fil[0]['f_S'] / 2.

        #========= select frequency range to be displayed =====================
        #=== shift, scale and select: W -> F, H_cplx -> H_c
        F = self.W * f_S2 / np.pi

        if fb.fil[0]['freqSpecsRangeType'] == 'sym':
            # shift H and F by f_S/2
            H = np.fft.fftshift(self.H_cmplx)
            F -= f_S2
        elif fb.fil[0]['freqSpecsRangeType'] == 'half':
            # only use the first half of H and F
            H = self.H_cmplx[0:params['N_FFT'] // 2]
            F = F[0:params['N_FFT'] // 2]
        else:  # fb.fil[0]['freqSpecsRangeType'] == 'whole'
            # use H and F as calculated
            H = self.H_cmplx

        y_str = r'$\angle H(\mathrm{e}^{\mathrm{j} \Omega})$ in '
        if self.unitPhi == 'rad':
            y_str += 'rad ' + r'$\rightarrow $'
            scale = 1.
        elif self.unitPhi == 'rad/pi':
            y_str += 'rad' + r'$ / \pi \;\rightarrow $'
            scale = 1. / np.pi
        else:
            y_str += 'deg ' + r'$\rightarrow $'
            scale = 180. / np.pi
        fb.fil[0]['plt_phiLabel'] = y_str
        fb.fil[0]['plt_phiUnit'] = self.unitPhi

        if self.chkWrap.isChecked():
            phi_plt = np.angle(H) * scale
        else:
            phi_plt = np.unwrap(np.angle(H)) * scale

        #---------------------------------------------------------
        self.ax.clear()  # need to clear, doesn't overwrite
        line_phi, = self.ax.plot(F, phi_plt)
        #---------------------------------------------------------

        self.ax.set_title(r'Phase Frequency Response')
        self.ax.set_xlabel(fb.fil[0]['plt_fLabel'])
        self.ax.set_ylabel(y_str)
        self.ax.set_xlim(fb.fil[0]['freqSpecsRange'])

        self.redraw()

#------------------------------------------------------------------------------

    def redraw(self):
        """
        Redraw the canvas when e.g. the canvas size has changed
        """
        self.mplwidget.redraw()
Esempio n. 4
0
class Plot_PZ(QWidget):
    # incoming, connected in sender widget (locally connected to self.process_sig_rx() )
    sig_rx = pyqtSignal(object)

    def __init__(self, parent):
        super(Plot_PZ, self).__init__(parent)
        self.needs_calc = True  # flag whether filter data has been changed
        self.needs_draw = False  # flag whether whether figure needs to be drawn
        # with new limits etc. (not implemented yet)
        self.tool_tip = "Pole / zero plan"
        self.tab_label = "P / Z"

        self._construct_UI()

#------------------------------------------------------------------------------

    def process_sig_rx(self, dict_sig=None):
        """
        Process signals coming from the navigation toolbar and from sig_rx
        """
        logger.debug("Processing {0} | needs_draw = {1}, visible = {2}"\
                     .format(dict_sig, self.needs_calc, self.isVisible()))
        if self.isVisible():
            if 'data_changed' in dict_sig or 'home' in dict_sig or self.needs_calc:
                self.draw()
                self.needs_calc = False
                self.needs_draw = False
            if 'view_changed' in dict_sig or self.needs_draw:
                self.update_view()
                self.needs_draw = False
        else:
            if 'data_changed' in dict_sig:
                self.needs_calc = True
            if 'view_changed' in dict_sig:
                self.needs_draw = True

#------------------------------------------------------------------------------

    def _construct_UI(self):
        """
        Intitialize the widget, consisting of:
        - Matplotlib widget with NavigationToolbar
        - Frame with control elements
        """
        self.chkHf = QCheckBox("Show |H(f)|", self)
        self.chkHf.setToolTip(
            "<span>Display |H(f)| around unit circle.</span>")
        self.chkHf.setEnabled(True)

        self.chkHfLog = QCheckBox("Log. Scale", self)
        self.chkHfLog.setToolTip("<span>Log. scale for |H(f)|.</span>")
        self.chkHfLog.setEnabled(True)

        self.diaRad_Hf = QDial(self)
        self.diaRad_Hf.setRange(2., 10.)
        self.diaRad_Hf.setValue(2)
        self.diaRad_Hf.setTracking(False)  # produce less events when turning
        self.diaRad_Hf.setFixedHeight(30)
        self.diaRad_Hf.setFixedWidth(30)
        self.diaRad_Hf.setWrapping(False)
        self.diaRad_Hf.setToolTip(
            "<span>Set max. radius for |H(f)| plot.</span>")

        self.lblRad_Hf = QLabel("Radius", self)

        self.chkFIR_P = QCheckBox("Plot FIR Poles", self)
        self.chkFIR_P.setToolTip("<span>Show FIR poles at the origin.</span>")
        self.chkFIR_P.setChecked(True)

        layHControls = QHBoxLayout()
        layHControls.addWidget(self.chkHf)
        layHControls.addWidget(self.chkHfLog)
        layHControls.addWidget(self.diaRad_Hf)
        layHControls.addWidget(self.lblRad_Hf)
        layHControls.addStretch(10)
        layHControls.addWidget(self.chkFIR_P)

        #----------------------------------------------------------------------
        #               ### frmControls ###
        #
        # This widget encompasses all control subwidgets
        #----------------------------------------------------------------------
        self.frmControls = QFrame(self)
        self.frmControls.setObjectName("frmControls")
        self.frmControls.setLayout(layHControls)

        #----------------------------------------------------------------------
        #               ### mplwidget ###
        #
        # main widget, encompassing the other widgets
        #----------------------------------------------------------------------
        self.mplwidget = MplWidget(self)
        self.mplwidget.layVMainMpl.addWidget(self.frmControls)
        self.mplwidget.layVMainMpl.setContentsMargins(*params['wdg_margins'])
        self.setLayout(self.mplwidget.layVMainMpl)

        self.init_axes()

        self.draw()  # calculate and draw poles and zeros

        #----------------------------------------------------------------------
        # GLOBAL SIGNALS & SLOTs
        #----------------------------------------------------------------------
        self.sig_rx.connect(self.process_sig_rx)
        #----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        #----------------------------------------------------------------------
        self.mplwidget.mplToolbar.sig_tx.connect(self.process_sig_rx)
        self.chkHf.clicked.connect(self.draw)
        self.chkHfLog.clicked.connect(self.draw)
        self.diaRad_Hf.valueChanged.connect(self.draw)
        self.chkFIR_P.clicked.connect(self.draw)

#------------------------------------------------------------------------------

    def init_axes(self):
        """
        Initialize and clear the axes (this is only run once)
        """
        if len(self.mplwidget.fig.get_axes()) == 0:  # empty figure, no axes
            self.ax = self.mplwidget.fig.subplots()  #.add_subplot(111)
        self.ax.get_xaxis().tick_bottom()  # remove axis ticks on top
        self.ax.get_yaxis().tick_left()  # remove axis ticks right

#------------------------------------------------------------------------------

    def update_view(self):
        """
        Draw the figure with new limits, scale etcs without recalculating H(f)
        -- not yet implemented, just use draw() for the moment
        """
        self.draw()

#------------------------------------------------------------------------------

    def draw(self):
        self.chkFIR_P.setVisible(fb.fil[0]['ft'] == 'FIR')
        self.draw_pz()

#------------------------------------------------------------------------------

    def draw_pz(self):
        """
        (re)draw P/Z plot
        """
        p_marker = params['P_Marker']
        z_marker = params['Z_Marker']

        zpk = fb.fil[0]['zpk']

        # add antiCausals if they exist (must take reciprocal to plot)
        if 'rpk' in fb.fil[0]:
            zA = fb.fil[0]['zpk'][0]
            zA = np.conj(1. / zA)
            pA = fb.fil[0]['zpk'][1]
            pA = np.conj(1. / pA)
            zC = np.append(zpk[0], zA)
            pC = np.append(zpk[1], pA)
            zpk[0] = zC
            zpk[1] = pC

        self.ax.clear()

        [z, p, k] = self.zplane(z=zpk[0],
                                p=zpk[1],
                                k=zpk[2],
                                plt_ax=self.ax,
                                plt_poles=self.chkFIR_P.isChecked()
                                or fb.fil[0]['ft'] == 'IIR',
                                mps=p_marker[0],
                                mpc=p_marker[1],
                                mzs=z_marker[0],
                                mzc=z_marker[1])

        self.ax.set_title(r'Pole / Zero Plot')
        self.ax.set_xlabel('Real axis')
        self.ax.set_ylabel('Imaginary axis')

        self.draw_Hf(r=self.diaRad_Hf.value())

        self.redraw()

#------------------------------------------------------------------------------

    def redraw(self):
        """
        Redraw the canvas when e.g. the canvas size has changed
        """
        self.mplwidget.redraw()

#------------------------------------------------------------------------------

    def zplane(self,
               b=None,
               a=1,
               z=None,
               p=None,
               k=1,
               pn_eps=1e-3,
               analog=False,
               plt_ax=None,
               plt_poles=True,
               style='square',
               anaCircleRad=0,
               lw=2,
               mps=10,
               mzs=10,
               mpc='r',
               mzc='b',
               plabel='',
               zlabel=''):
        """
        Plot the poles and zeros in the complex z-plane either from the
        coefficients (`b,`a) of a discrete transfer function `H`(`z`) (zpk = False)
        or directly from the zeros and poles (z,p) (zpk = True).

        When only b is given, an FIR filter with all poles at the origin is assumed.

        Parameters
        ----------
        b :  array_like
             Numerator coefficients (transversal part of filter)
             When b is not None, poles and zeros are determined from the coefficients
             b and a

        a :  array_like (optional, default = 1 for FIR-filter)
             Denominator coefficients (recursive part of filter)

        z :  array_like, default = None
             Zeros
             When b is None, poles and zeros are taken directly from z and p

        p :  array_like, default = None
             Poles

        analog : boolean (default: False)
            When True, create a P/Z plot suitable for the s-plane, i.e. suppress
            the unit circle (unless anaCircleRad > 0) and scale the plot for
            a good display of all poles and zeros.

        pn_eps : float (default : 1e-2)
             Tolerance for separating close poles or zeros

        plt_ax : handle to axes for plotting (default: None)
            When no axes is specified, the current axes is determined via plt.gca()

        plt_poles : Boolean (default : True)
            Plot poles. This can be used to suppress poles for FIR systems
            where all poles are at the origin.

        style : string (default: 'square')
            Style of the plot, for style == 'square' make scale of x- and y-
            axis equal.

        mps : integer  (default: 10)
            Size for pole marker

        mzs : integer (default: 10)
            Size for zero marker

        mpc : char (default: 'r')
            Pole marker colour

        mzc : char (default: 'b')
            Zero marker colour

        lw : integer (default:  2)
            Linewidth for unit circle

        plabel, zlabel : string (default: '')
            This string is passed to the plot command for poles and zeros and
            can be displayed by legend()


        Returns
        -------
        z, p, k : ndarray


        Notes
        -----
        """
        # TODO:
        # - polar option
        # - add keywords for color of circle -> **kwargs
        # - add option for multi-dimensional arrays and zpk data

        # make sure that all inputs are arrays
        b = np.atleast_1d(b)
        a = np.atleast_1d(a)
        z = np.atleast_1d(z)  # make sure that p, z  are arrays
        p = np.atleast_1d(p)

        if b.any():  # coefficients were specified
            if len(b) < 2 and len(a) < 2:
                logger.error(
                    'No proper filter coefficients: both b and a are scalars!')
                return z, p, k

            # The coefficients are less than 1, normalize the coefficients
            if np.max(b) > 1:
                kn = np.max(b)
                b = b / float(kn)
            else:
                kn = 1.

            if np.max(a) > 1:
                kd = np.max(a)
                a = a / abs(kd)
            else:
                kd = 1.

            # Calculate the poles, zeros and scaling factor
            p = np.roots(a)
            z = np.roots(b)
            k = kn / kd
        elif not (len(p) or len(z)):  # P/Z were specified
            logger.error('Either b,a or z,p must be specified!')
            return z, p, k

        # find multiple poles and zeros and their multiplicities
        if len(p) < 2:  # single pole, [None] or [0]
            if not p or p == 0:  # only zeros, create equal number of poles at origin
                p = np.array(0, ndmin=1)  #
                num_p = np.atleast_1d(len(z))
            else:
                num_p = [1.]  # single pole != 0
        else:
            #p, num_p = sig.signaltools.unique_roots(p, tol = pn_eps, rtype='avg')
            p, num_p = unique_roots(p, tol=pn_eps, rtype='avg')
    #        p = np.array(p); num_p = np.ones(len(p))
        if len(z) > 0:
            z, num_z = unique_roots(z, tol=pn_eps, rtype='avg')

    #        z = np.array(z); num_z = np.ones(len(z))
    #z, num_z = sig.signaltools.unique_roots(z, tol = pn_eps, rtype='avg')
        else:
            num_z = []

        ax = plt_ax  #.subplot(111)
        if analog == False:
            # create the unit circle for the z-plane
            uc = patches.Circle((0, 0),
                                radius=1,
                                fill=False,
                                color='grey',
                                ls='solid',
                                zorder=1)
            ax.add_patch(uc)
            if style == 'square':
                #r = 1.1
                #ax.axis([-r, r, -r, r]) # overridden by next option
                ax.axis('equal')
        #    ax.spines['left'].set_position('center')
        #    ax.spines['bottom'].set_position('center')
        #    ax.spines['right'].set_visible(True)
        #    ax.spines['top'].set_visible(True)

        else:  # s-plane
            if anaCircleRad > 0:
                # plot a circle with radius = anaCircleRad
                uc = patches.Circle((0, 0),
                                    radius=anaCircleRad,
                                    fill=False,
                                    color='grey',
                                    ls='solid',
                                    zorder=1)
                ax.add_patch(uc)
            # plot real and imaginary axis
            ax.axhline(lw=2, color='k', zorder=1)
            ax.axvline(lw=2, color='k', zorder=1)

        # Plot the zeros
        ax.scatter(z.real,
                   z.imag,
                   s=mzs * mzs,
                   zorder=2,
                   marker='o',
                   facecolor='none',
                   edgecolor=mzc,
                   lw=lw,
                   label=zlabel)
        # and print their multiplicity
        for i in range(len(z)):
            logger.debug('z: {0} | {1} | {2}'.format(i, z[i], num_z[i]))
            if num_z[i] > 1:
                ax.text(np.real(z[i]),
                        np.imag(z[i]),
                        '  (' + str(num_z[i]) + ')',
                        va='top',
                        color=mzc)
        if plt_poles:
            # Plot the poles
            ax.scatter(p.real,
                       p.imag,
                       s=mps * mps,
                       zorder=2,
                       marker='x',
                       color=mpc,
                       lw=lw,
                       label=plabel)
            # and print their multiplicity
            for i in range(len(p)):
                logger.debug('p:{0} | {1} | {2}'.format(i, p[i], num_p[i]))
                if num_p[i] > 1:
                    ax.text(np.real(p[i]),
                            np.imag(p[i]),
                            '  (' + str(num_p[i]) + ')',
                            va='bottom',
                            color=mpc)

# =============================================================================
#            # increase distance between ticks and labels
#            # to give some room for poles and zeros
#         for tick in ax.get_xaxis().get_major_ticks():
#             tick.set_pad(12.)
#             tick.label1 = tick._get_text1()
#         for tick in ax.get_yaxis().get_major_ticks():
#             tick.set_pad(12.)
#             tick.label1 = tick._get_text1()
#
# =============================================================================
        xl = ax.get_xlim()
        Dx = max(abs(xl[1] - xl[0]), 0.05)
        yl = ax.get_ylim()
        Dy = max(abs(yl[1] - yl[0]), 0.05)
        ax.set_xlim((xl[0] - Dx * 0.05, max(xl[1] + Dx * 0.05, 0)))
        ax.set_ylim((yl[0] - Dy * 0.05, yl[1] + Dy * 0.05))

        return z, p, k

#------------------------------------------------------------------------------

    def draw_Hf(self, r=2):
        """
        Draw the magnitude frequency response around the UC
        """
        # suppress "divide by zero in log10" warnings
        old_settings_seterr = np.seterr()
        np.seterr(divide='ignore')

        self.chkHfLog.setVisible(self.chkHf.isChecked())
        self.diaRad_Hf.setVisible(self.chkHf.isChecked())
        self.lblRad_Hf.setVisible(self.chkHf.isChecked())
        if not self.chkHf.isChecked():
            return
        ba = fb.fil[0]['ba']
        w, H = sig.freqz(ba[0], ba[1], worN=params['N_FFT'], whole=True)
        H = np.abs(H)
        if self.chkHfLog.isChecked():
            H = np.clip(np.log10(H), -6, None)  # clip to -120 dB
            H = H - np.max(H)  # shift scale to H_min ... 0
            H = 1 + (r - 1) * (1 + H / abs(np.min(H)))  # scale to 1 ... r
        else:
            H = 1 + (r - 1) * H / np.max(H)  #  map |H(f)| to a range 1 ... r
        y = H * np.sin(w)
        x = H * np.cos(w)

        self.ax.plot(x, y, label="|H(f)|")
        uc = patches.Circle((0, 0),
                            radius=r,
                            fill=False,
                            color='grey',
                            ls='dashed',
                            zorder=1)
        self.ax.add_patch(uc)

        xl = self.ax.get_xlim()
        xmax = max(abs(xl[0]), abs(xl[1]), r * 1.05)
        yl = self.ax.get_ylim()
        ymax = max(abs(yl[0]), abs(yl[1]), r * 1.05)
        self.ax.set_xlim((-xmax, xmax))
        self.ax.set_ylim((-ymax, ymax))

        np.seterr(**old_settings_seterr)
Esempio n. 5
0
class Plot_Hf(QWidget):
    """
    Widget for plotting \|H(f)\|, frequency specs and the phase
    """
    # incoming, connected in sender widget (locally connected to self.process_sig_rx() )
    sig_rx = pyqtSignal(object)

    def __init__(self, parent):
        super(Plot_Hf, self).__init__(parent)
        self.needs_calc = True  # flag whether plot needs to be updated
        self.needs_draw = True  # flag whether plot needs to be redrawn
        self.tool_tip = "Magnitude and phase frequency response"
        self.tab_label = "|H(f)|"

        self.log_bottom = -80
        self.lin_neg_bottom = -10

        self._construct_ui()

#------------------------------------------------------------------------------

    def process_sig_rx(self, dict_sig=None):
        """
        Process signals coming from the navigation toolbar and from sig_rx
        """
        logger.debug("SIG_RX - needs_calc = {0}, vis = {1}\n{2}"\
                     .format(self.needs_calc, self.isVisible(), pprint_log(dict_sig)))

        if self.isVisible():
            if 'data_changed' in dict_sig or 'specs_changed' in dict_sig\
                    or 'home' in dict_sig or self.needs_calc:
                self.draw()
                self.needs_calc = False
                self.needs_draw = False
            if 'view_changed' in dict_sig or self.needs_draw:
                self.update_view()
                self.needs_draw = False
        else:
            if 'data_changed' in dict_sig or 'specs_changed' in dict_sig:
                self.needs_calc = True
            if 'view_changed' in dict_sig:
                self.needs_draw = True

    def _construct_ui(self):
        """
        Define and construct the subwidgets
        """
        modes = ['| H |', 're{H}', 'im{H}']
        self.cmbShowH = QComboBox(self)
        self.cmbShowH.addItems(modes)
        self.cmbShowH.setObjectName("cmbUnitsH")
        self.cmbShowH.setToolTip(
            "Show magnitude, real / imag. part of H or H \n"
            "without linear phase (acausal system).")
        self.cmbShowH.setCurrentIndex(0)

        self.lblIn = QLabel("in", self)

        units = ['dB', 'V', 'W', 'Auto']
        self.cmbUnitsA = QComboBox(self)
        self.cmbUnitsA.addItems(units)
        self.cmbUnitsA.setObjectName("cmbUnitsA")
        self.cmbUnitsA.setToolTip(
            "<span>Set unit for y-axis:\n"
            "dB is attenuation (positive values), V and W are gain (less than 1).</span>"
        )
        self.cmbUnitsA.setCurrentIndex(0)

        self.lbl_log_bottom = QLabel("Bottom", self)
        self.led_log_bottom = QLineEdit(self)
        self.led_log_bottom.setText(str(self.log_bottom))
        self.led_log_bottom.setToolTip(
            "<span>Minimum display value for dB. scale.</span>")
        self.lbl_log_unit = QLabel("dB", self)

        self.cmbShowH.setSizeAdjustPolicy(QComboBox.AdjustToContents)
        self.cmbUnitsA.setSizeAdjustPolicy(QComboBox.AdjustToContents)

        self.chkZerophase = QCheckBox("Zero phase", self)
        self.chkZerophase.setToolTip(
            "<span>Remove linear phase calculated from filter order.\n"
            "Attention: This makes no sense for a non-linear phase system!</span>"
        )

        self.lblInset = QLabel("Inset", self)
        self.cmbInset = QComboBox(self)
        self.cmbInset.addItems(['off', 'edit', 'fixed'])
        self.cmbInset.setObjectName("cmbInset")
        self.cmbInset.setToolTip("Display/edit second inset plot")
        self.cmbInset.setCurrentIndex(0)
        self.inset_idx = 0  # store previous index for comparison

        self.chkSpecs = QCheckBox("Specs", self)
        self.chkSpecs.setChecked(False)
        self.chkSpecs.setToolTip("Display filter specs as hatched regions")

        self.chkPhase = QCheckBox("Phase", self)
        self.chkPhase.setToolTip("Overlay phase")
        self.chkPhase.setChecked(False)

        self.chkAlign = QCheckBox("Align", self)
        self.chkAlign.setToolTip(
            "<span>Try to align grids for magnitude and phase "
            "(doesn't work in all cases).</span>")
        self.chkAlign.setChecked(True)
        self.chkAlign.setVisible(self.chkPhase.isChecked())

        #----------------------------------------------------------------------
        #               ### frmControls ###
        #
        # This widget encompasses all control subwidgets
        #----------------------------------------------------------------------
        layHControls = QHBoxLayout()
        layHControls.addStretch(10)
        layHControls.addWidget(self.cmbShowH)
        layHControls.addWidget(self.lblIn)
        layHControls.addWidget(self.cmbUnitsA)
        layHControls.addStretch(1)
        layHControls.addWidget(self.lbl_log_bottom)
        layHControls.addWidget(self.led_log_bottom)
        layHControls.addWidget(self.lbl_log_unit)
        layHControls.addStretch(1)
        layHControls.addWidget(self.chkZerophase)
        layHControls.addStretch(1)
        layHControls.addWidget(self.lblInset)
        layHControls.addWidget(self.cmbInset)
        layHControls.addStretch(1)
        layHControls.addWidget(self.chkSpecs)
        layHControls.addStretch(1)
        layHControls.addWidget(self.chkPhase)
        layHControls.addWidget(self.chkAlign)
        layHControls.addStretch(10)

        self.frmControls = QFrame(self)
        self.frmControls.setObjectName("frmControls")
        self.frmControls.setLayout(layHControls)

        #----------------------------------------------------------------------
        #               ### mplwidget ###
        #
        # main widget, encompassing the other widgets
        #----------------------------------------------------------------------
        self.mplwidget = MplWidget(self)
        self.mplwidget.layVMainMpl.addWidget(self.frmControls)
        self.mplwidget.layVMainMpl.setContentsMargins(*params['wdg_margins'])
        self.mplwidget.mplToolbar.a_he.setEnabled(True)
        self.mplwidget.mplToolbar.a_he.info = "manual/plot_hf.html"
        self.setLayout(self.mplwidget.layVMainMpl)

        self.init_axes()

        self.draw()  # calculate and draw |H(f)|

        #----------------------------------------------------------------------
        # GLOBAL SIGNALS & SLOTs
        #----------------------------------------------------------------------
        self.sig_rx.connect(self.process_sig_rx)
        #----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        #----------------------------------------------------------------------
        self.cmbUnitsA.currentIndexChanged.connect(self.draw)
        self.led_log_bottom.editingFinished.connect(self.update_view)
        self.cmbShowH.currentIndexChanged.connect(self.draw)

        self.chkZerophase.clicked.connect(self.draw)
        self.cmbInset.currentIndexChanged.connect(self.draw_inset)

        self.chkSpecs.clicked.connect(self.draw)
        self.chkPhase.clicked.connect(self.draw)
        self.chkAlign.clicked.connect(self.draw)

        self.mplwidget.mplToolbar.sig_tx.connect(self.process_sig_rx)

#------------------------------------------------------------------------------

    def init_axes(self):
        """
        Initialize and clear the axes (this is run only once)
        """
        if len(self.mplwidget.fig.get_axes()) == 0:  # empty figure, no axes
            self.ax = self.mplwidget.fig.subplots()
        self.ax.xaxis.tick_bottom()  # remove axis ticks on top
        self.ax.yaxis.tick_left()  # remove axis ticks right

#------------------------------------------------------------------------------

    def align_y_axes(self, ax1, ax2):
        """ Sets tick marks of twinx axes to line up with total number of
            ax1 tick marks
            """

        ax1_ylims = ax1.get_ybound()
        # collect only visible ticks
        ax1_yticks = [
            t for t in ax1.get_yticks()
            if t >= ax1_ylims[0] and t <= ax1_ylims[1]
        ]
        ax1_nticks = len(ax1_yticks)
        ax1_ydelta_lim = ax1_ylims[1] - ax1_ylims[0]  # span of limits
        ax1_ydelta_vis = ax1_yticks[-1] - ax1_yticks[
            0]  # delta of max. and min tick
        ax1_yoffset = ax1_yticks[0] - ax1_ylims[
            0]  # offset between lower limit and first tick

        # calculate scale of Delta Limits / Delta Ticks
        ax1_scale = ax1_ydelta_lim / ax1_ydelta_vis

        ax2_ylims = ax2.get_ybound()
        ax2_yticks = ax2.get_yticks()
        ax2_nticks = len(ax2_yticks)
        #ax2_ydelta_lim = ax2_ylims[1] - ax2_ylims[0]
        ax2_ydelta_vis = ax2_yticks[-1] - ax2_yticks[0]
        ax2_ydelta_lim = ax2_ydelta_vis * ax1_scale
        ax2_scale = ax2_ydelta_lim / ax2_ydelta_vis
        # calculate new offset between lower limit and first tick
        ax2_yoffset = ax1_yoffset * ax2_ydelta_lim / ax1_ydelta_lim
        logger.warning("ax2: delta_vis: {0}, scale: {1}, offset: {2}".format(
            ax2_ydelta_vis, ax2_scale, ax2_yoffset))
        logger.warning("Ticks: {0} # {1}".format(ax1_nticks, ax2_nticks))

        ax2.set_yticks(
            np.linspace(ax2_yticks[0], (ax2_yticks[1] - ax2_yticks[0]),
                        ax1_nticks))
        logger.warning("ax2[0]={0} | ax2[1]={1} ax2[-1]={2}".format(
            ax2_yticks[0], ax2_yticks[1], ax2_yticks[-1]))
        ax2_lim0 = ax2_yticks[0] - ax2_yoffset
        ax2.set_ybound(ax2_lim0, ax2_lim0 + ax2_ydelta_lim)

# =============================================================================
#             # https://stackoverflow.com/questions/26752464/how-do-i-align-gridlines-for-two-y-axis-scales-using-matplotlib
#             # works, but both axes have ugly numbers
#             nticks = 11
#             ax.yaxis.set_major_locator(ticker.LinearLocator(nticks))
#             self.ax_p.yaxis.set_major_locator(ticker.LinearLocator(nticks))
# # =============================================================================
# =============================================================================
#             # https://stackoverflow.com/questions/45037386/trouble-aligning-ticks-for-matplotlib-twinx-axes
#             # works, but second axis has ugly numbering
#             l_H = ax.get_ylim()
#             l_p = self.ax_p.get_ylim()
#             f = lambda x : l_p[0]+(x-l_H[0])/(l_H[1]-l_H[0])*(l_p[1]-l_p[0])
#             ticks = f(ax.get_yticks())
#             self.ax_p.yaxis.set_major_locator(ticker.FixedLocator(ticks))
#
# =============================================================================

# http://stackoverflow.com/questions/28692608/align-grid-lines-on-two-plots
# http://stackoverflow.com/questions/3654619/matplotlib-multiple-y-axes-grid-lines-applied-to-both
# http://stackoverflow.com/questions/20243683/matplotlib-align-twinx-tick-marks
# manual setting:
#self.ax_p.set_yticks( np.linspace(self.ax_p.get_ylim()[0],self.ax_p.get_ylim()[1],nbins) )
#ax1.set_yticks(np.linspace(ax1.get_ybound()[0], ax1.get_ybound()[1], 5))
#ax2.set_yticks(np.linspace(ax2.get_ybound()[0], ax2.get_ybound()[1], 5))
#http://stackoverflow.com/questions/3654619/matplotlib-multiple-y-axes-grid-lines-applied-to-both

# use helper functions from matplotlib.ticker:
#   MaxNLocator: set no more than nbins + 1 ticks
#self.ax_p.yaxis.set_major_locator( matplotlib.ticker.MaxNLocator(nbins = nbins) )
# further options: integer = False,
#                   prune = [‘lower’ | ‘upper’ | ‘both’ | None] Remove edge ticks
#   AutoLocator:
#self.ax_p.yaxis.set_major_locator( matplotlib.ticker.AutoLocator() )
#   LinearLocator:
#self.ax_p.yaxis.set_major_locator( matplotlib.ticker.LinearLocator(numticks = nbins -1 ) )

#            self.ax_p.locator_params(axis = 'y', nbins = nbins)
#
#            self.ax_p.set_yticks(np.linspace(self.ax_p.get_ybound()[0],
#                                             self.ax_p.get_ybound()[1],
#                                             len(self.ax.get_yticks())-1))

#N = source_ax.xaxis.get_major_ticks()
#target_ax.xaxis.set_major_locator(LinearLocator(N))

#------------------------------------------------------------------------------

    def plot_spec_limits(self, ax):
        """
        Plot the specifications limits (F_SB, A_SB, ...) as hatched areas with borders.
        """
        hatch = params['mpl_hatch']
        hatch_borders = params['mpl_hatch_border']

        def dB(lin):
            return 20 * np.log10(lin)

        def _plot_specs():
            # upper limits:
            ax.plot(F_lim_upl, A_lim_upl, F_lim_upc, A_lim_upc, F_lim_upr,
                    A_lim_upr, **hatch_borders)
            if A_lim_upl:
                ax.fill_between(F_lim_upl, max(A_lim_upl), A_lim_upl, **hatch)
            if A_lim_upc:
                ax.fill_between(F_lim_upc, max(A_lim_upc), A_lim_upc, **hatch)
            if A_lim_upr:
                ax.fill_between(F_lim_upr, max(A_lim_upr), A_lim_upr, **hatch)
            # lower limits:
            ax.plot(F_lim_lol, A_lim_lol, F_lim_loc, A_lim_loc, F_lim_lor,
                    A_lim_lor, **hatch_borders)
            if A_lim_lol:
                ax.fill_between(F_lim_lol, min(A_lim_lol), A_lim_lol, **hatch)
            if A_lim_loc:
                ax.fill_between(F_lim_loc, min(A_lim_loc), A_lim_loc, **hatch)
            if A_lim_lor:
                ax.fill_between(F_lim_lor, min(A_lim_lor), A_lim_lor, **hatch)

        if self.unitA == 'V':
            exp = 1.
        elif self.unitA == 'W':
            exp = 2.

        if self.unitA == 'dB':
            if fb.fil[0]['ft'] == "FIR":
                A_PB_max = dB(1 + self.A_PB)
                A_PB2_max = dB(1 + self.A_PB2)
            else:  # IIR dB
                A_PB_max = A_PB2_max = 0

            A_PB_min = dB(1 - self.A_PB)
            A_PB2_min = dB(1 - self.A_PB2)
            A_PB_minx = min(A_PB_min, A_PB2_min) - 5
            A_PB_maxx = max(A_PB_max, A_PB2_max) + 5

            A_SB = dB(self.A_SB)
            A_SB2 = dB(self.A_SB2)
            A_SB_maxx = max(A_SB, A_SB2) + 10
        else:  # 'V' or 'W'
            if fb.fil[0]['ft'] == "FIR":
                A_PB_max = (1 + self.A_PB)**exp
                A_PB2_max = (1 + self.A_PB2)**exp
            else:  # IIR lin
                A_PB_max = A_PB2_max = 1

            A_PB_min = (1 - self.A_PB)**exp
            A_PB2_min = (1 - self.A_PB2)**exp
            A_PB_minx = min(A_PB_min, A_PB2_min) / 1.05
            A_PB_maxx = max(A_PB_max, A_PB2_max) * 1.05

            A_SB = self.A_SB**exp
            A_SB2 = self.A_SB2**exp
            A_SB_maxx = A_PB_min / 10.

        F_max = self.f_max / 2
        F_PB = self.F_PB
        F_SB = fb.fil[0]['F_SB'] * self.f_max
        F_SB2 = fb.fil[0]['F_SB2'] * self.f_max
        F_PB2 = fb.fil[0]['F_PB2'] * self.f_max

        F_lim_upl = F_lim_lol = []  # left side limits, lower and upper
        A_lim_upl = A_lim_lol = []

        F_lim_upc = F_lim_loc = []  # center limits, lower and upper
        A_lim_upc = A_lim_loc = []

        F_lim_upr = F_lim_lor = []  # right side limits, lower and upper
        A_lim_upr = A_lim_lor = []

        if fb.fil[0]['rt'] == 'LP':
            F_lim_upl = [0, F_PB, F_PB]
            A_lim_upl = [A_PB_max, A_PB_max, A_PB_maxx]
            F_lim_lol = F_lim_upl
            A_lim_lol = [A_PB_min, A_PB_min, A_PB_minx]

            F_lim_upr = [F_SB, F_SB, F_max]
            A_lim_upr = [A_SB_maxx, A_SB, A_SB]

        if fb.fil[0]['rt'] == 'HP':
            F_lim_upl = [0, F_SB, F_SB]
            A_lim_upl = [A_SB, A_SB, A_SB_maxx]

            F_lim_upr = [F_PB, F_PB, F_max]
            A_lim_upr = [A_PB_maxx, A_PB_max, A_PB_max]
            F_lim_lor = F_lim_upr
            A_lim_lor = [A_PB_minx, A_PB_min, A_PB_min]

        if fb.fil[0]['rt'] == 'BS':
            F_lim_upl = [0, F_PB, F_PB]
            A_lim_upl = [A_PB_max, A_PB_max, A_PB_maxx]
            F_lim_lol = F_lim_upl
            A_lim_lol = [A_PB_min, A_PB_min, A_PB_minx]

            F_lim_upc = [F_SB, F_SB, F_SB2, F_SB2]
            A_lim_upc = [A_SB_maxx, A_SB, A_SB, A_SB_maxx]

            F_lim_upr = [F_PB2, F_PB2, F_max]
            A_lim_upr = [A_PB_maxx, A_PB2_max, A_PB2_max]
            F_lim_lor = F_lim_upr
            A_lim_lor = [A_PB_minx, A_PB2_min, A_PB2_min]

        if fb.fil[0]['rt'] == 'BP':
            F_lim_upl = [0, F_SB, F_SB]
            A_lim_upl = [A_SB, A_SB, A_SB_maxx]

            F_lim_upc = [F_PB, F_PB, F_PB2, F_PB2]
            A_lim_upc = [A_PB_maxx, A_PB_max, A_PB_max, A_PB_maxx]
            F_lim_loc = F_lim_upc
            A_lim_loc = [A_PB_minx, A_PB_min, A_PB_min, A_PB_minx]

            F_lim_upr = [F_SB2, F_SB2, F_max]
            A_lim_upr = [A_SB_maxx, A_SB2, A_SB2]

        if fb.fil[0]['rt'] == 'HIL':
            F_lim_upc = [F_PB, F_PB, F_PB2, F_PB2]
            A_lim_upc = [A_PB_maxx, A_PB_max, A_PB_max, A_PB_maxx]

            F_lim_loc = F_lim_upc
            A_lim_loc = [A_PB_minx, A_PB_min, A_PB_min, A_PB_minx]

        F_lim_upr = np.array(F_lim_upr)
        F_lim_lor = np.array(F_lim_lor)
        F_lim_upl = np.array(F_lim_upl)
        F_lim_lol = np.array(F_lim_lol)
        F_lim_upc = np.array(F_lim_upc)
        F_lim_loc = np.array(F_lim_loc)

        _plot_specs()  # plot specs in the range 0 ... f_S/2

        if fb.fil[0]['freqSpecsRangeType'] != 'half':
            # add plot limits for other half of the spectrum
            if fb.fil[0][
                    'freqSpecsRangeType'] == 'sym':  # frequency axis +/- f_S/2
                F_lim_upl = -F_lim_upl
                F_lim_lol = -F_lim_lol
                F_lim_upc = -F_lim_upc
                F_lim_loc = -F_lim_loc
                F_lim_upr = -F_lim_upr
                F_lim_lor = -F_lim_lor
            else:  # -> 'whole'
                F_lim_upl = self.f_max - F_lim_upl
                F_lim_lol = self.f_max - F_lim_lol
                F_lim_upc = self.f_max - F_lim_upc
                F_lim_loc = self.f_max - F_lim_loc
                F_lim_upr = self.f_max - F_lim_upr
                F_lim_lor = self.f_max - F_lim_lor

            _plot_specs()

#------------------------------------------------------------------------------

    def draw_inset(self):
        """
        Construct / destruct second axes for an inset second plot
        """
        # TODO:  try   ax1 = zoomed_inset_axes(ax, 6, loc=1) # zoom = 6
        # TODO: choose size & position of inset, maybe dependent on filter type
        #        or specs (i.e. where is passband etc.)

        # DEBUG
        #            print(self.cmbInset.currentIndex(), self.mplwidget.fig.axes) # list of axes in Figure
        #            for ax in self.mplwidget.fig.axes:
        #                print(ax)
        #                print("cmbInset, inset_idx:",self.cmbInset.currentIndex(), self.inset_idx)

        if self.cmbInset.currentIndex() > 0:
            if self.inset_idx == 0:
                # Inset was turned off before, create a new one
                #  Add an axes at position rect [left, bottom, width, height]:
                self.ax_i = self.mplwidget.fig.add_axes([0.65, 0.61, .3, .3])
                self.ax_i.clear()  # clear old plot and specs

                # draw an opaque background with the extent of the inset plot:
                #                self.ax_i.patch.set_facecolor('green') # without label area
                #                self.mplwidget.fig.patch.set_facecolor('green') # whole figure
                extent = self.mplwidget.get_full_extent(self.ax_i, pad=0.0)
                # Transform this back to figure coordinates - otherwise, it
                #  won't behave correctly when the size of the plot is changed:
                extent = extent.transformed(
                    self.mplwidget.fig.transFigure.inverted())
                rect = Rectangle((extent.xmin, extent.ymin),
                                 extent.width,
                                 extent.height,
                                 facecolor=rcParams['figure.facecolor'],
                                 edgecolor='none',
                                 transform=self.mplwidget.fig.transFigure,
                                 zorder=-1)
                self.ax_i.patches.append(rect)

                self.ax_i.set_xlim(fb.fil[0]['freqSpecsRange'])
                self.ax_i.plot(self.F, self.H_plt)

            if self.cmbInset.currentIndex() == 1:  # edit / navigate inset
                self.ax_i.set_navigate(True)
                self.ax.set_navigate(False)
                if self.chkSpecs.isChecked():
                    self.plot_spec_limits(self.ax_i)
            else:  # edit / navigate main plot
                self.ax_i.set_navigate(False)
                self.ax.set_navigate(True)
        else:  # inset has been turned off, delete it
            self.ax.set_navigate(True)
            try:
                #remove ax_i from the figure
                self.mplwidget.fig.delaxes(self.ax_i)
            except AttributeError:
                pass

        self.inset_idx = self.cmbInset.currentIndex()  # update index
        self.draw()

#------------------------------------------------------------------------------

    def draw_phase(self, ax):
        """
        Draw phase on second y-axis in the axes system passed as the argument
        """
        if hasattr(self, 'ax_p'):
            self.mplwidget.fig.delaxes(self.ax_p)
            del self.ax_p
        # try:
        #     self.mplwidget.fig.delaxes(self.ax_p)
        # except (KeyError, AttributeError):
        #     pass

        if self.chkPhase.isChecked():
            self.ax_p = ax.twinx(
            )  # second axes system with same x-axis for phase
            self.ax_p.is_twin = True  # mark this as 'twin' to suppress second grid in mpl_widget
            #
            phi_str = r'$\angle H(\mathrm{e}^{\mathrm{j} \Omega})$'
            if fb.fil[0]['plt_phiUnit'] == 'rad':
                phi_str += ' in rad ' + r'$\rightarrow $'
                scale = 1.
            elif fb.fil[0]['plt_phiUnit'] == 'rad/pi':
                phi_str += ' in rad' + r'$ / \pi \;\rightarrow $'
                scale = 1. / np.pi
            else:
                phi_str += ' in deg ' + r'$\rightarrow $'
                scale = 180. / np.pi

            # replace nan and inf by finite values, otherwise np.unwrap yields
            # an array full of nans
            phi = np.angle(np.nan_to_num(self.H_c))
            #-----------------------------------------------------------
            self.ax_p.plot(self.F,
                           np.unwrap(phi) * scale,
                           'g-.',
                           label="Phase")
            #-----------------------------------------------------------
            self.ax_p.set_ylabel(phi_str)

#------------------------------------------------------------------------------

    def calc_hf(self):
        """
        (Re-)Calculate the complex frequency response H(f)
        """

        # calculate H_cmplx(W) (complex) for W = 0 ... 2 pi:
        self.W, self.H_cmplx = calc_Hcomplex(fb.fil[0], params['N_FFT'], True)

#------------------------------------------------------------------------------

    def draw(self):
        """
        Re-calculate \|H(f)\| and draw the figure
        """
        self.chkAlign.setVisible(self.chkPhase.isChecked())
        self.calc_hf()
        self.update_view()

#------------------------------------------------------------------------------

    def update_view(self):
        """
        Draw the figure with new limits, scale etc without recalculating H(f)
        """
        # suppress "divide by zero in log10" warnings
        old_settings_seterr = np.seterr()
        np.seterr(divide='ignore')

        # Get corners for spec display from the parameters of the target specs subwidget
        try:
            param_list = fb.fil_tree[fb.fil[0]['rt']][fb.fil[0]['ft']]\
                                    [fb.fil[0]['fc']][fb.fil[0]['fo']]['tspecs'][1]['amp']
        except KeyError:
            param_list = []

        SB = [l for l in param_list if 'A_SB' in l]
        PB = [l for l in param_list if 'A_PB' in l]

        if SB:
            A_min = min([fb.fil[0][l] for l in SB])
        else:
            A_min = 5e-4

        if PB:
            A_max = max([fb.fil[0][l] for l in PB])
        else:
            A_max = 1

        if np.all(self.W) is None:  # H(f) has not been calculated yet
            self.calc_hf()

        if self.cmbUnitsA.currentText() == 'Auto':
            self.unitA = fb.fil[0]['amp_specs_unit']
        else:
            self.unitA = self.cmbUnitsA.currentText()

        # only display log bottom widget for unit dB
        self.lbl_log_bottom.setVisible(self.unitA == 'dB')
        self.led_log_bottom.setVisible(self.unitA == 'dB')
        self.lbl_log_unit.setVisible(self.unitA == 'dB')

        # Linphase settings only makes sense for amplitude plot and
        # for plottin real/imag. part of H, not its magnitude
        self.chkZerophase.setCheckable(self.unitA == 'V')
        self.chkZerophase.setEnabled(self.unitA == 'V')

        self.specs = self.chkSpecs.isChecked()

        self.f_max = fb.fil[0]['f_max']

        self.F_PB = fb.fil[0]['F_PB'] * self.f_max
        self.f_maxB = fb.fil[0]['F_SB'] * self.f_max

        self.A_PB = fb.fil[0]['A_PB']
        self.A_PB2 = fb.fil[0]['A_PB2']
        self.A_SB = fb.fil[0]['A_SB']
        self.A_SB2 = fb.fil[0]['A_SB2']

        f_lim = fb.fil[0]['freqSpecsRange']

        #========= select frequency range to be displayed =====================
        #=== shift, scale and select: W -> F, H_cplx -> H_c
        self.F = self.W / (2 * np.pi) * self.f_max

        if fb.fil[0]['freqSpecsRangeType'] == 'sym':
            # shift H and F by f_S/2
            self.H_c = np.fft.fftshift(self.H_cmplx)
            self.F -= self.f_max / 2.
        elif fb.fil[0]['freqSpecsRangeType'] == 'half':
            # only use the first half of H and F
            self.H_c = self.H_cmplx[0:params['N_FFT'] // 2]
            self.F = self.F[0:params['N_FFT'] // 2]
        else:  # fb.fil[0]['freqSpecsRangeType'] == 'whole'
            # use H and F as calculated
            self.H_c = self.H_cmplx

        # now calculate mag / real / imaginary part of H_c:
        if self.chkZerophase.isChecked():  # remove the linear phase
            self.H_c = self.H_c * np.exp(
                1j * self.W[0:len(self.F)] * fb.fil[0]["N"] / 2.)

        if self.cmbShowH.currentIndex() == 0:  # show magnitude of H
            H = abs(self.H_c)
            H_str = r'$|H(\mathrm{e}^{\mathrm{j} \Omega})|$'
        elif self.cmbShowH.currentIndex() == 1:  # show real part of H
            H = self.H_c.real
            H_str = r'$\Re \{H(\mathrm{e}^{\mathrm{j} \Omega})\}$'
        else:  # show imag. part of H
            H = self.H_c.imag
            H_str = r'$\Im \{H(\mathrm{e}^{\mathrm{j} \Omega})\}$'

        #================ Main Plotting Routine =========================
        #===  clear the axes and (re)draw the plot (if selectable)
        if self.ax.get_navigate():

            if self.unitA == 'dB':
                self.log_bottom = safe_eval(self.led_log_bottom.text(),
                                            self.log_bottom,
                                            return_type='float',
                                            sign='neg')
                self.led_log_bottom.setText(str(self.log_bottom))

                self.H_plt = np.maximum(20 * np.log10(abs(H)), self.log_bottom)
                A_lim = [self.log_bottom, 2]
                H_str += ' in dB ' + r'$\rightarrow$'
            elif self.unitA == 'V':  #  'lin'
                self.H_plt = H
                if self.cmbShowH.currentIndex(
                ) != 0:  # H can be less than zero
                    A_min = max(self.lin_neg_bottom,
                                np.nanmin(self.H_plt[np.isfinite(self.H_plt)]))
                else:
                    A_min = 0
                A_lim = [A_min, (1.05 + A_max)]
                H_str += ' in V ' + r'$\rightarrow $'
                self.ax.axhline(linewidth=1, color='k')  # horizontal line at 0
            else:  # unit is W
                A_lim = [0, (1.03 + A_max)**2.]
                self.H_plt = H * H.conj()
                H_str += ' in W ' + r'$\rightarrow $'

            #logger.debug("lim: {0}, min: {1}, max: {2} - {3}".format(A_lim, A_min, A_max, self.H_plt[0]))

            #-----------------------------------------------------------
            self.ax.clear()
            self.ax.plot(self.F, self.H_plt, label='H(f)')
            # TODO: self.draw_inset() # this gives an infinite recursion
            self.draw_phase(self.ax)
            #-----------------------------------------------------------

            #============= Set Limits and draw specs =========================
            if self.chkSpecs.isChecked():
                self.plot_spec_limits(self.ax)

            #     self.ax_bounds = [self.ax.get_ybound()[0], self.ax.get_ybound()[1]]#, self.ax.get]
            self.ax.set_xlim(f_lim)
            self.ax.set_ylim(A_lim)
            # logger.warning("set limits")

            self.ax.set_xlabel(fb.fil[0]['plt_fLabel'])
            self.ax.set_ylabel(H_str)
            if self.chkPhase.isChecked():
                self.ax.set_title(r'Magnitude and Phase Frequency Response')
            else:
                self.ax.set_title(r'Magnitude Frequency Response')
            self.ax.xaxis.set_minor_locator(
                AutoMinorLocator())  # enable minor ticks
            self.ax.yaxis.set_minor_locator(
                AutoMinorLocator())  # enable minor ticks

            np.seterr(**old_settings_seterr)

        self.redraw()

#------------------------------------------------------------------------------

    def redraw(self):
        """
        Redraw the canvas when e.g. the canvas size has changed
        """
        if hasattr(self, 'ax_p') and self.chkAlign.isChecked():
            # Align gridlines between H(f) and phi nicely
            self.align_y_axes(self.ax, self.ax_p)
        self.mplwidget.redraw()
Esempio n. 6
0
class Plot_FFT_win(QDialog):
    """
    Create a pop-up widget for displaying time and frequency view of an FFT
    window.

    Data is passed via the dictionary `win_dict` that is passed during construction.
    """
    # incoming
    sig_rx = pyqtSignal(object)
    # outgoing
    sig_tx = pyqtSignal(object)

    def __init__(self,
                 parent,
                 win_dict=fb.fil[0]['win_fft'],
                 sym=True,
                 title='pyFDA Window Viewer'):
        super(Plot_FFT_win, self).__init__(parent)

        self.needs_calc = True
        self.needs_draw = True
        self.needs_redraw = True

        self.bottom_f = -80  # min. value for dB display
        self.bottom_t = -60
        self.N = 32  # initial number of data points
        self.N_auto = win_dict['win_len']

        self.pad = 16  # amount of zero padding

        self.win_dict = win_dict
        self.sym = sym

        self.tbl_rows = 2
        self.tbl_cols = 6
        # initial settings for checkboxes
        self.tbl_sel = [True, True, False, False]

        self.setAttribute(Qt.WA_DeleteOnClose)
        self.setWindowTitle(title)
        self._construct_UI()

        qwindow_stay_on_top(self, True)

#------------------------------------------------------------------------------

    def closeEvent(self, event):
        """
        Catch closeEvent (user has tried to close the window) and send a
        signal to parent where window closing is registered before actually
        closing the window.
        """
        self.sig_tx.emit({'sender': __name__, 'closeEvent': ''})
        event.accept()

#------------------------------------------------------------------------------

    def process_sig_rx(self, dict_sig=None):
        """
        Process signals coming from the navigation toolbar and from sig_rx
        """
        logger.debug("PROCESS_SIG_RX - vis: {0}\n{1}"\
                     .format(self.isVisible(), pprint_log(dict_sig)))
        if ('view_changed' in dict_sig and dict_sig['view_changed'] == 'win')\
            or ('filt_changed' in dict_sig and dict_sig['filt_changed'] == 'firwin')\
            or self.needs_calc:
            # logger.warning("Auto: {0} - WinLen: {1}".format(self.N_auto, self.win_dict['win_len']))
            self.N_auto = self.win_dict['win_len']
            self.calc_N()

            if self.isVisible():
                self.draw()
                self.needs_calc = False
            else:
                self.needs_calc = True

        elif 'home' in dict_sig:
            self.update_view()

        else:
            logger.error("Unknown content of dict_sig: {0}".format(dict_sig))

#------------------------------------------------------------------------------

    def _construct_UI(self):
        """
        Intitialize the widget, consisting of:
        - Matplotlib widget with NavigationToolbar
        - Frame with control elements
        """
        self.bfont = QFont()
        self.bfont.setBold(True)

        self.chk_auto_N = QCheckBox(self)
        self.chk_auto_N.setChecked(False)
        self.chk_auto_N.setToolTip(
            "Use number of points from calling routine.")

        self.lbl_auto_N = QLabel("Auto " + to_html("N", frmt='i'))

        self.led_N = QLineEdit(self)
        self.led_N.setText(str(self.N))
        self.led_N.setMaximumWidth(70)
        self.led_N.setToolTip("<span>Number of window data points.</span>")

        self.chk_log_t = QCheckBox("Log", self)
        self.chk_log_t.setChecked(False)
        self.chk_log_t.setToolTip("Display in dB")

        self.led_log_bottom_t = QLineEdit(self)
        self.led_log_bottom_t.setText(str(self.bottom_t))
        self.led_log_bottom_t.setMaximumWidth(50)
        self.led_log_bottom_t.setEnabled(self.chk_log_t.isChecked())
        self.led_log_bottom_t.setToolTip(
            "<span>Minimum display value for log. scale.</span>")

        self.lbl_log_bottom_t = QLabel("dB", self)
        self.lbl_log_bottom_t.setEnabled(self.chk_log_t.isChecked())

        self.chk_norm_f = QCheckBox("Norm", self)
        self.chk_norm_f.setChecked(True)
        self.chk_norm_f.setToolTip(
            "Normalize window spectrum for a maximum of 1.")

        self.chk_half_f = QCheckBox("Half", self)
        self.chk_half_f.setChecked(True)
        self.chk_half_f.setToolTip(
            "Display window spectrum in the range 0 ... 0.5 f_S.")

        self.chk_log_f = QCheckBox("Log", self)
        self.chk_log_f.setChecked(True)
        self.chk_log_f.setToolTip("Display in dB")

        self.led_log_bottom_f = QLineEdit(self)
        self.led_log_bottom_f.setText(str(self.bottom_f))
        self.led_log_bottom_f.setMaximumWidth(50)
        self.led_log_bottom_f.setEnabled(self.chk_log_f.isChecked())
        self.led_log_bottom_f.setToolTip(
            "<span>Minimum display value for log. scale.</span>")

        self.lbl_log_bottom_f = QLabel("dB", self)
        self.lbl_log_bottom_f.setEnabled(self.chk_log_f.isChecked())

        layHControls = QHBoxLayout()
        layHControls.addWidget(self.chk_auto_N)
        layHControls.addWidget(self.lbl_auto_N)
        layHControls.addWidget(self.led_N)
        layHControls.addStretch(1)
        layHControls.addWidget(self.chk_log_t)
        layHControls.addWidget(self.led_log_bottom_t)
        layHControls.addWidget(self.lbl_log_bottom_t)
        layHControls.addStretch(10)
        layHControls.addWidget(self.chk_norm_f)
        layHControls.addStretch(1)
        layHControls.addWidget(self.chk_half_f)
        layHControls.addStretch(1)
        layHControls.addWidget(self.chk_log_f)
        layHControls.addWidget(self.led_log_bottom_f)
        layHControls.addWidget(self.lbl_log_bottom_f)

        self.tblWinProperties = QTableWidget(self.tbl_rows, self.tbl_cols,
                                             self)
        self.tblWinProperties.setAlternatingRowColors(True)
        self.tblWinProperties.verticalHeader().setVisible(False)
        self.tblWinProperties.horizontalHeader().setVisible(False)
        self._init_table(self.tbl_rows, self.tbl_cols, " ")

        self.txtInfoBox = QTextBrowser(self)

        #----------------------------------------------------------------------
        #               ### frmControls ###
        #
        # This widget encompasses all control subwidgets
        #----------------------------------------------------------------------
        self.frmControls = QFrame(self)
        self.frmControls.setObjectName("frmControls")
        self.frmControls.setLayout(layHControls)

        #----------------------------------------------------------------------
        #               ### mplwidget ###
        #
        # main widget: Layout layVMainMpl (VBox) is defined with MplWidget,
        #              additional widgets can be added (like self.frmControls)
        #              The widget encompasses all other widgets.
        #----------------------------------------------------------------------
        self.mplwidget = MplWidget(self)
        self.mplwidget.layVMainMpl.addWidget(self.frmControls)
        self.mplwidget.layVMainMpl.setContentsMargins(*params['wdg_margins'])

        #----------------------------------------------------------------------
        #               ### frmInfo ###
        #
        # This widget encompasses the text info box and the table with window
        # parameters.
        #----------------------------------------------------------------------
        layVInfo = QVBoxLayout(self)
        layVInfo.addWidget(self.tblWinProperties)
        layVInfo.addWidget(self.txtInfoBox)

        self.frmInfo = QFrame(self)
        self.frmInfo.setObjectName("frmInfo")
        self.frmInfo.setLayout(layVInfo)

        #----------------------------------------------------------------------
        #               ### splitter ###
        #
        # This widget encompasses all control subwidgets
        #----------------------------------------------------------------------

        splitter = QSplitter(self)
        splitter.setOrientation(Qt.Vertical)
        splitter.addWidget(self.mplwidget)
        splitter.addWidget(self.frmInfo)

        # setSizes uses absolute pixel values, but can be "misused" by specifying values
        # that are way too large: in this case, the space is distributed according
        # to the _ratio_ of the values:
        splitter.setSizes([3000, 1000])

        layVMain = QVBoxLayout()
        layVMain.addWidget(splitter)
        self.setLayout(layVMain)

        #----------------------------------------------------------------------
        #           Set subplots
        #
        self.ax = self.mplwidget.fig.subplots(nrows=1, ncols=2)
        self.ax_t = self.ax[0]
        self.ax_f = self.ax[1]

        self.draw()  # initial drawing

        #----------------------------------------------------------------------
        # GLOBAL SIGNALS & SLOTs
        #----------------------------------------------------------------------
        self.sig_rx.connect(self.process_sig_rx)

        #----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        #----------------------------------------------------------------------
        self.chk_log_f.clicked.connect(self.update_view)
        self.chk_log_t.clicked.connect(self.update_view)
        self.led_log_bottom_t.editingFinished.connect(self.update_bottom)
        self.led_log_bottom_f.editingFinished.connect(self.update_bottom)

        self.chk_auto_N.clicked.connect(self.calc_N)
        self.led_N.editingFinished.connect(self.draw)

        self.chk_norm_f.clicked.connect(self.draw)
        self.chk_half_f.clicked.connect(self.update_view)

        self.mplwidget.mplToolbar.sig_tx.connect(self.process_sig_rx)
        self.tblWinProperties.itemClicked.connect(self._handle_item_clicked)
#------------------------------------------------------------------------------

    def _init_table(self, rows, cols, val):
        for r in range(rows):
            for c in range(cols):
                item = QTableWidgetItem(val)
                if c % 3 == 0:
                    item.setFlags(Qt.ItemIsUserCheckable | Qt.ItemIsEnabled)
                    if self.tbl_sel[r * 2 + c % 3]:
                        item.setCheckState(Qt.Checked)
                    else:
                        item.setCheckState(Qt.Unchecked)
                self.tblWinProperties.setItem(r, c, item)
#   https://stackoverflow.com/questions/12366521/pyqt-checkbox-in-qtablewidget

#------------------------------------------------------------------------------

    def _set_table_item(self, row, col, val, font=None, sel=None):
        """
        Set the table item with the index `row, col` and the value val
        """
        item = self.tblWinProperties.item(row, col)
        item.setText(str(val))

        if font:
            self.tblWinProperties.item(row, col).setFont(font)

        if sel == True:
            item.setCheckState(Qt.Checked)
        if sel == False:
            item.setCheckState(Qt.Unchecked)
        # when sel is not specified, don't change anything

#------------------------------------------------------------------------------

    def _handle_item_clicked(self, item):
        if item.column() % 3 == 0:  # clicked on checkbox
            num = item.row() * 2 + item.column() // 3
            if item.checkState() == Qt.Checked:
                self.tbl_sel[num] = True
                logger.debug('"{0}:{1}" Checked'.format(item.text(), num))
            else:
                self.tbl_sel[num] = False
                logger.debug('"{0}:{1}" Unchecked'.format(item.text(), num))

        elif item.column() % 3 == 1:  # clicked on value field
            logger.info("{0:s} copied to clipboard.".format(item.text()))
            fb.clipboard.setText(item.text())

        self.update_view()

#------------------------------------------------------------------------------

    def update_bottom(self):
        """
        Update log bottom settings
        """
        self.bottom_t = safe_eval(self.led_log_bottom_t.text(),
                                  self.bottom_t,
                                  sign='neg',
                                  return_type='float')
        self.led_log_bottom_t.setText(str(self.bottom_t))

        self.bottom_f = safe_eval(self.led_log_bottom_f.text(),
                                  self.bottom_f,
                                  sign='neg',
                                  return_type='float')
        self.led_log_bottom_f.setText(str(self.bottom_f))

        self.update_view()

#------------------------------------------------------------------------------

    def calc_N(self):
        """
        (Re-)Calculate the number of data points when Auto N chkbox has been
        clicked or when the number of data points has been updated outside this
        class
        """
        if self.chk_auto_N.isChecked():
            self.N = self.N_auto

        self.draw()

#------------------------------------------------------------------------------

    def calc_win(self):
        """
        (Re-)Calculate the window and its FFT
        """
        self.led_N.setEnabled(not self.chk_auto_N.isChecked())

        if not self.chk_auto_N.isChecked():
            self.N = safe_eval(self.led_N.text(),
                               self.N,
                               sign='pos',
                               return_type='int')

    # else:
    #self.N = self.win_dict['win_len']

        self.led_N.setText(str(self.N))

        self.n = np.arange(self.N)

        self.win = calc_window_function(self.win_dict,
                                        self.win_dict['name'],
                                        self.N,
                                        sym=self.sym)

        self.nenbw = self.N * np.sum(np.square(self.win)) / (np.square(
            np.sum(self.win)))
        self.cgain = np.sum(self.win) / self.N

        self.F = fftfreq(self.N * self.pad,
                         d=1. / fb.fil[0]['f_S'])  # use zero padding
        self.Win = np.abs(fft(self.win, self.N * self.pad))
        if self.chk_norm_f.isChecked():
            self.Win /= (self.N * self.cgain
                         )  # correct gain for periodic signals (coherent gain)

        first_zero = argrelextrema(self.Win[:(self.N * self.pad) // 2],
                                   np.less)
        if np.shape(first_zero)[1] > 0:
            first_zero = first_zero[0][0]
            self.first_zero_f = self.F[first_zero]
            self.sidelobe_level = np.max(
                self.Win[first_zero:(self.N * self.pad) // 2])
        else:
            self.first_zero_f = np.nan
            self.sidelobe_level = 0

#------------------------------------------------------------------------------

    def draw(self):
        """
        Main entry point:
        Re-calculate \|H(f)\| and draw the figure
        """
        self.calc_win()
        self.update_view()

#------------------------------------------------------------------------------

    def update_view(self):
        """
        Draw the figure with new limits, scale etc without recalculating the
        window.
        """
        # suppress "divide by zero in log10" warnings
        old_settings_seterr = np.seterr()
        np.seterr(divide='ignore')

        self.ax_t.cla()
        self.ax_f.cla()

        self.ax_t.set_xlabel(fb.fil[0]['plt_tLabel'])
        self.ax_t.set_ylabel(r'$w[n] \; \rightarrow$')

        self.ax_f.set_xlabel(fb.fil[0]['plt_fLabel'])
        self.ax_f.set_ylabel(r'$W(f) \; \rightarrow$')

        if self.chk_log_t.isChecked():
            self.ax_t.plot(
                self.n,
                np.maximum(20 * np.log10(np.abs(self.win)), self.bottom_t))
        else:
            self.ax_t.plot(self.n, self.win)

        if self.chk_half_f.isChecked():
            F = self.F[:len(self.F * self.pad) // 2]
            Win = self.Win[:len(self.F * self.pad) // 2]
        else:
            F = fftshift(self.F)
            Win = fftshift(self.Win)

        if self.chk_log_f.isChecked():
            self.ax_f.plot(
                F, np.maximum(20 * np.log10(np.abs(Win)), self.bottom_f))
            self.nenbw_disp = 10 * np.log10(self.nenbw)
            self.cgain_disp = 20 * np.log10(self.cgain)
            self.sidelobe_level_disp = 20 * np.log10(self.sidelobe_level)
            self.unit_nenbw = "dB"
            self.unit_scale = "dB"
        else:
            self.ax_f.plot(F, Win)
            self.nenbw_disp = self.nenbw
            self.cgain_disp = self.cgain
            self.sidelobe_level_disp = self.sidelobe_level
            self.unit_nenbw = "bins"
            self.unit_scale = ""

        self.led_log_bottom_t.setEnabled(self.chk_log_t.isChecked())
        self.lbl_log_bottom_t.setEnabled(self.chk_log_t.isChecked())
        self.led_log_bottom_f.setEnabled(self.chk_log_f.isChecked())
        self.lbl_log_bottom_f.setEnabled(self.chk_log_f.isChecked())

        window_name = self.win_dict['name']
        param_txt = ""
        if self.win_dict['n_par'] > 0:
            param_txt = " (" + self.win_dict['par'][0][
                'name_tex'] + " = {0:.3g})".format(
                    self.win_dict['par'][0]['val'])
        if self.win_dict['n_par'] > 1:
            param_txt = param_txt[:-1]\
                + ", {0:s} = {1:.3g})".format(self.win_dict['par'][1]['name_tex'], self.win_dict['par'][1]['val'])

        self.mplwidget.fig.suptitle(r'{0} Window'.format(window_name) +
                                    param_txt)

        # plot a line at the max. sidelobe level
        if self.tbl_sel[3]:
            self.ax_f.axhline(self.sidelobe_level_disp, ls='dotted', c='b')

        patch = mpl_patches.Rectangle((0, 0),
                                      1,
                                      1,
                                      fc="white",
                                      ec="white",
                                      lw=0,
                                      alpha=0)
        # Info legend for time domain window
        labels_t = []
        labels_t.append("$N$ = {0:d}".format(self.N))
        self.ax_t.legend([patch],
                         labels_t,
                         loc='best',
                         fontsize='small',
                         fancybox=True,
                         framealpha=0.7,
                         handlelength=0,
                         handletextpad=0)

        # Info legend for frequency domain window
        labels_f = []
        N_patches = 0
        if self.tbl_sel[0]:
            labels_f.append("$NENBW$ = {0:.4g} {1}".format(
                self.nenbw_disp, self.unit_nenbw))
            N_patches += 1
        if self.tbl_sel[1]:
            labels_f.append("$CGAIN$ = {0:.4g} {1}".format(
                self.cgain_disp, self.unit_scale))
            N_patches += 1
        if self.tbl_sel[2]:
            labels_f.append("1st Zero = {0:.4g}".format(self.first_zero_f))
            N_patches += 1
        if N_patches > 0:
            self.ax_f.legend([patch] * N_patches,
                             labels_f,
                             loc='best',
                             fontsize='small',
                             fancybox=True,
                             framealpha=0.7,
                             handlelength=0,
                             handletextpad=0)
        np.seterr(**old_settings_seterr)

        self.update_info()
        self.redraw()

#------------------------------------------------------------------------------

    def update_info(self):
        """
        Update the text info box for the window
        """
        if 'info' in self.win_dict:
            self.txtInfoBox.setText(self.win_dict['info'])

        self._set_table_item(0, 0, "ENBW", font=self.bfont)  #, sel=True)
        self._set_table_item(0, 1, "{0:.5g}".format(self.nenbw_disp))
        self._set_table_item(0, 2, self.unit_nenbw)
        self._set_table_item(0, 3, "Scale", font=self.bfont)  #, sel=True)
        self._set_table_item(0, 4, "{0:.5g}".format(self.cgain_disp))
        self._set_table_item(0, 5, self.unit_scale)

        self._set_table_item(1, 0, "1st Zero", font=self.bfont)  #, sel=True)
        self._set_table_item(1, 1, "{0:.5g}".format(self.first_zero_f))
        self._set_table_item(1, 2, "f_S")

        self._set_table_item(1, 3, "Sidelobes", font=self.bfont)  #, sel=True)
        self._set_table_item(1, 4, "{0:.5g}".format(self.sidelobe_level_disp))
        self._set_table_item(1, 5, self.unit_scale)

        self.tblWinProperties.resizeColumnsToContents()
        self.tblWinProperties.resizeRowsToContents()
#------------------------------------------------------------------------------

    def redraw(self):
        """
        Redraw the canvas when e.g. the canvas size has changed
        """
        self.mplwidget.redraw()
        self.needs_redraw = False
Esempio n. 7
0
    def _construct_UI(self):
        """
        Intitialize the widget, consisting of:
        - Matplotlib widget with NavigationToolbar
        - Frame with control elements
        """
        self.bfont = QFont()
        self.bfont.setBold(True)

        self.qfft_win_select = QFFTWinSelector(self, self.win_dict)

        self.lbl_N = QLabel(to_html("N =", frmt='bi'))
        self.led_N = QLineEdit(self)
        self.led_N.setText(str(self.N_view))
        self.led_N.setMaximumWidth(qtext_width(N_x=8))
        self.led_N.setToolTip(
            "<span>Number of window data points to display.</span>")

        # By default, the enter key triggers the default 'dialog action' in QDialog
        # widgets. This activates one of the pushbuttons.
        self.but_log_t = QPushButton("dB", default=False, autoDefault=False)
        self.but_log_t.setMaximumWidth(qtext_width(" dB "))
        self.but_log_t.setObjectName("chk_log_time")
        self.but_log_t.setCheckable(True)
        self.but_log_t.setChecked(False)
        self.but_log_t.setToolTip("Display in dB")

        self.led_log_bottom_t = QLineEdit(self)
        self.led_log_bottom_t.setVisible(self.but_log_t.isChecked())
        self.led_log_bottom_t.setText(str(self.bottom_t))
        self.led_log_bottom_t.setMaximumWidth(qtext_width(N_x=6))
        self.led_log_bottom_t.setToolTip(
            "<span>Minimum display value for log. scale.</span>")

        self.lbl_log_bottom_t = QLabel(to_html("min =", frmt='bi'), self)
        self.lbl_log_bottom_t.setVisible(self.but_log_t.isChecked())

        self.but_norm_f = QPushButton("Max=1",
                                      default=False,
                                      autoDefault=False)
        self.but_norm_f.setCheckable(True)
        self.but_norm_f.setChecked(True)
        self.but_norm_f.setMaximumWidth(qtext_width(text=" Max=1 "))
        self.but_norm_f.setToolTip(
            "Normalize window spectrum for a maximum of 1.")

        self.but_half_f = QPushButton("0...½",
                                      default=False,
                                      autoDefault=False)
        self.but_half_f.setCheckable(True)
        self.but_half_f.setChecked(True)
        self.but_half_f.setMaximumWidth(qtext_width(text=" 0...½ "))
        self.but_half_f.setToolTip(
            "Display window spectrum in the range 0 ... 0.5 f_S.")

        # By default, the enter key triggers the default 'dialog action' in QDialog
        # widgets. This activates one of the pushbuttons.
        self.but_log_f = QPushButton("dB", default=False, autoDefault=False)
        self.but_log_f.setMaximumWidth(qtext_width(" dB "))
        self.but_log_f.setObjectName("chk_log_freq")
        self.but_log_f.setToolTip("<span>Display in dB.</span>")
        self.but_log_f.setCheckable(True)
        self.but_log_f.setChecked(True)

        self.lbl_log_bottom_f = QLabel(to_html("min =", frmt='bi'), self)
        self.lbl_log_bottom_f.setVisible(self.but_log_f.isChecked())

        self.led_log_bottom_f = QLineEdit(self)
        self.led_log_bottom_f.setVisible(self.but_log_t.isChecked())
        self.led_log_bottom_f.setText(str(self.bottom_f))
        self.led_log_bottom_f.setMaximumWidth(qtext_width(N_x=6))
        self.led_log_bottom_f.setToolTip(
            "<span>Minimum display value for log. scale.</span>")

        # ----------------------------------------------------------------------
        #               ### frmControls ###
        #
        # This widget encompasses all control subwidgets
        # ----------------------------------------------------------------------
        layH_win_select = QHBoxLayout()
        layH_win_select.addWidget(self.qfft_win_select)
        layH_win_select.setContentsMargins(0, 0, 0, 0)
        layH_win_select.addStretch(1)
        frmQFFT = QFrame(self)
        frmQFFT.setObjectName("frmQFFT")
        frmQFFT.setLayout(layH_win_select)

        hline = QHLine()

        layHControls = QHBoxLayout()
        layHControls.addWidget(self.lbl_N)
        layHControls.addWidget(self.led_N)
        layHControls.addStretch(1)
        layHControls.addWidget(self.lbl_log_bottom_t)
        layHControls.addWidget(self.led_log_bottom_t)
        layHControls.addWidget(self.but_log_t)
        layHControls.addStretch(5)
        layHControls.addWidget(QVLine(width=2))
        layHControls.addStretch(5)
        layHControls.addWidget(self.but_norm_f)
        layHControls.addStretch(1)
        layHControls.addWidget(self.but_half_f)
        layHControls.addStretch(1)
        layHControls.addWidget(self.lbl_log_bottom_f)
        layHControls.addWidget(self.led_log_bottom_f)
        layHControls.addWidget(self.but_log_f)

        layVControls = QVBoxLayout()
        layVControls.addWidget(frmQFFT)
        layVControls.addWidget(hline)
        layVControls.addLayout(layHControls)

        frmControls = QFrame(self)
        frmControls.setObjectName("frmControls")
        frmControls.setLayout(layVControls)

        # ----------------------------------------------------------------------
        #               ### mplwidget ###
        #
        # Layout layVMainMpl (VBox) is defined within MplWidget, additional
        # widgets can be added below the matplotlib widget (here: frmControls)
        #
        # ----------------------------------------------------------------------
        self.mplwidget = MplWidget(self)
        self.mplwidget.layVMainMpl.addWidget(frmControls)
        self.mplwidget.layVMainMpl.setContentsMargins(0, 0, 0, 0)

        # ----------------------------------------------------------------------
        #               ### frmInfo ###
        #
        # This widget encompasses the text info box and the table with window
        # parameters.
        # ----------------------------------------------------------------------
        self.tbl_win_props = QTableWidget(self.tbl_rows, self.tbl_cols, self)
        self.tbl_win_props.setAlternatingRowColors(True)
        # Auto-resize of table can be set using the header (although it is invisible)
        self.tbl_win_props.verticalHeader().setSectionResizeMode(
            QHeaderView.Stretch)
        # Only the columns with data are stretched, the others are minimum size
        self.tbl_win_props.horizontalHeader().setSectionResizeMode(
            1, QHeaderView.Stretch)
        self.tbl_win_props.horizontalHeader().setSectionResizeMode(
            4, QHeaderView.Stretch)
        self.tbl_win_props.verticalHeader().setVisible(False)
        self.tbl_win_props.horizontalHeader().setVisible(False)
        self.tbl_win_props.setSizePolicy(QSizePolicy.MinimumExpanding,
                                         QSizePolicy.MinimumExpanding)
        self.tbl_win_props.setFixedHeight(
            self.tbl_win_props.rowHeight(0) * self.tbl_rows +
            self.tbl_win_props.frameWidth() * 2)
        # self.tbl_win_props.setVerticalScrollBarPolicy(
        #     Qt.ScrollBarAlwaysOff)
        # self.tbl_win_props.setHorizontalScrollBarPolicy(
        #     Qt.ScrollBarAlwaysOff)

        self._construct_table(self.tbl_rows, self.tbl_cols, " ")

        self.txtInfoBox = QTextBrowser(self)

        layVInfo = QVBoxLayout(self)
        layVInfo.addWidget(self.tbl_win_props)
        layVInfo.addWidget(self.txtInfoBox)

        frmInfo = QFrame(self)
        frmInfo.setObjectName("frmInfo")
        frmInfo.setLayout(layVInfo)

        # ----------------------------------------------------------------------
        #               ### splitter ###
        #
        # This widget encompasses all subwidgets
        # ----------------------------------------------------------------------

        splitter = QSplitter(self)
        splitter.setOrientation(Qt.Vertical)
        splitter.addWidget(self.mplwidget)
        splitter.addWidget(frmInfo)

        # setSizes uses absolute pixel values, but can be "misused" by
        # specifying values that are way too large: in this case, the space
        # is distributed according to the _ratio_ of the values:
        splitter.setSizes([3000, 800])

        layVMain = QVBoxLayout()
        layVMain.addWidget(splitter)
        self.setLayout(layVMain)

        # ----------------------------------------------------------------------
        #           Set subplots
        #
        self.ax = self.mplwidget.fig.subplots(nrows=1, ncols=2)
        self.ax_t = self.ax[0]
        self.ax_f = self.ax[1]

        self.calc_win_draw()  # initial calculation and drawing

        # ----------------------------------------------------------------------
        # GLOBAL SIGNALS & SLOTs
        # ----------------------------------------------------------------------
        self.sig_rx.connect(self.process_sig_rx)
        self.sig_rx.connect(self.qfft_win_select.sig_rx)

        # ----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        # ----------------------------------------------------------------------
        self.but_log_f.clicked.connect(self.update_view)
        self.but_log_t.clicked.connect(self.update_view)
        self.led_log_bottom_t.editingFinished.connect(self.update_bottom)
        self.led_log_bottom_f.editingFinished.connect(self.update_bottom)

        self.led_N.editingFinished.connect(self.calc_win_draw)

        self.but_norm_f.clicked.connect(self.calc_win_draw)
        self.but_half_f.clicked.connect(self.update_view)

        self.mplwidget.mplToolbar.sig_tx.connect(self.process_sig_rx)
        self.tbl_win_props.itemClicked.connect(self._handle_item_clicked)

        self.qfft_win_select.sig_tx.connect(self.update_fft_win)
Esempio n. 8
0
class Plot_PZ(QWidget):
    # incoming, connected in sender widget (locally connected to self.process_sig_rx() )
    sig_rx = pyqtSignal(object)

    def __init__(self):
        super().__init__()
        self.needs_calc = True   # flag whether filter data has been changed
        self.needs_draw = False  # flag whether whether figure needs to be drawn
                                 # with new limits etc. (not implemented yet)
        self.tool_tip = "Pole / zero plan"
        self.tab_label = "P / Z"

        self.cmb_overlay_items = [
            "<span>Add various overlays to P/Z diagram.</span>",
            ("none", "None", ""),
            ("h(f)", "|H(f)|",
             "<span>Show |H(f)| wrapped around the unit circle between 0 resp. -120 dB "
             "and max(H(f)).</span>"),
            ("contour", "Contour", "<span>Show contour lines for |H(z)|</span>"),
            ("contourf", "Contourf", "<span>Show filled contours for |H(z)|</span>"),
            ]
        self.cmb_overlay_default = "none"  # default setting
        self.cmap = "viridis"  # colormap

        self.zmin = 0
        self.zmax = 2
        self.zmin_dB = -80
        self.zmax_dB = np.round(20 * np.log10(self.zmax), 2)
        self._construct_UI()

# ------------------------------------------------------------------------------
    def process_sig_rx(self, dict_sig: dict = None) -> None:
        """
        Process signals coming from the navigation toolbar and from sig_rx
        """
        # logger.info("Processing {0} | needs_draw = {1}, visible = {2}"\
        #              .format(dict_sig, self.needs_calc, self.isVisible()))
        if self.isVisible():
            if 'data_changed' in dict_sig or 'home' in dict_sig or self.needs_calc:
                self.draw()
                self.needs_calc = False
                self.needs_draw = False
            elif 'view_changed' in dict_sig or self.needs_draw:
                self.update_view()
                self.needs_draw = False
            elif 'ui_changed' in dict_sig and dict_sig['ui_changed'] == 'resized':
                self.draw()
        else:
            if 'data_changed' in dict_sig:
                self.needs_calc = True
            elif 'view_changed' in dict_sig:
                self.needs_draw = True
            elif 'ui_changed' in dict_sig and dict_sig['ui_changed'] == 'resized':
                self.needs_draw = True

# ------------------------------------------------------------------------------
    def _construct_UI(self):
        """
        Intitialize the widget, consisting of:
        - Matplotlib widget with NavigationToolbar
        - Frame with control elements
        """
        self.lbl_overlay = QLabel(to_html("Overlay:", frmt='bi'), self)
        self.cmb_overlay = QComboBox(self)
        qcmb_box_populate(
            self.cmb_overlay, self.cmb_overlay_items, self.cmb_overlay_default)

        self.but_log = PushButton(" Log.", checked=True)
        self.but_log.setObjectName("but_log")
        self.but_log.setToolTip("<span>Log. scale for overlays.</span>")

        self.diaRad_Hf = QDial(self)
        self.diaRad_Hf.setRange(2, 10)
        self.diaRad_Hf.setValue(2)
        self.diaRad_Hf.setTracking(False)  # produce less events when turning
        self.diaRad_Hf.setFixedHeight(30)
        self.diaRad_Hf.setFixedWidth(30)
        self.diaRad_Hf.setWrapping(False)
        self.diaRad_Hf.setToolTip("<span>Set max. radius for |H(f)| plot.</span>")

        self.lblRad_Hf = QLabel("Radius", self)

        self.lblBottom = QLabel(to_html("Bottom =", frmt='bi'), self)
        self.ledBottom = QLineEdit(self)
        self.ledBottom.setObjectName("ledBottom")
        self.ledBottom.setText(str(self.zmin))
        self.ledBottom.setMaximumWidth(qtext_width(N_x=8))
        self.ledBottom.setToolTip("Minimum display value.")
        self.lblBottomdB = QLabel("dB", self)
        self.lblBottomdB.setVisible(self.but_log.isChecked())

        self.lblTop = QLabel(to_html("Top =", frmt='bi'), self)
        self.ledTop = QLineEdit(self)
        self.ledTop.setObjectName("ledTop")
        self.ledTop.setText(str(self.zmax))
        self.ledTop.setToolTip("Maximum display value.")
        self.ledTop.setMaximumWidth(qtext_width(N_x=8))
        self.lblTopdB = QLabel("dB", self)
        self.lblTopdB.setVisible(self.but_log.isChecked())

        self.but_fir_poles = PushButton(" FIR Poles ", checked=True)
        self.but_fir_poles.setToolTip("<span>Show FIR poles at the origin.</span>")

        layHControls = QHBoxLayout()
        layHControls.addWidget(self.lbl_overlay)
        layHControls.addWidget(self.cmb_overlay)
        layHControls.addWidget(self.but_log)
        layHControls.addWidget(self.diaRad_Hf)
        layHControls.addWidget(self.lblRad_Hf)
        layHControls.addWidget(self.lblTop)
        layHControls.addWidget(self.ledTop)
        layHControls.addWidget(self.lblTopdB)
        layHControls.addWidget(self.lblBottom)
        layHControls.addWidget(self.ledBottom)
        layHControls.addWidget(self.lblBottomdB)
        layHControls.addStretch(10)
        layHControls.addWidget(self.but_fir_poles)

        # ----------------------------------------------------------------------
        #               ### frmControls ###
        #
        # This widget encompasses all control subwidgets
        # ----------------------------------------------------------------------
        self.frmControls = QFrame(self)
        self.frmControls.setObjectName("frmControls")
        self.frmControls.setLayout(layHControls)

        # ----------------------------------------------------------------------
        #               ### mplwidget ###
        #
        # main widget, encompassing the other widgets
        # ----------------------------------------------------------------------
        self.mplwidget = MplWidget(self)
        self.mplwidget.layVMainMpl.addWidget(self.frmControls)
        self.mplwidget.layVMainMpl.setContentsMargins(*params['wdg_margins'])
        self.mplwidget.mplToolbar.a_he.setEnabled(True)
        self.mplwidget.mplToolbar.a_he.info = "manual/plot_pz.html"
        self.setLayout(self.mplwidget.layVMainMpl)

        self.init_axes()

        self._log_clicked()  # calculate and draw poles and zeros

        # ----------------------------------------------------------------------
        # GLOBAL SIGNALS & SLOTs
        # ----------------------------------------------------------------------
        self.sig_rx.connect(self.process_sig_rx)
        # ----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        # ----------------------------------------------------------------------
        self.mplwidget.mplToolbar.sig_tx.connect(self.process_sig_rx)
        self.cmb_overlay.currentIndexChanged.connect(self.draw)
        self.but_log.clicked.connect(self._log_clicked)
        self.ledBottom.editingFinished.connect(self._log_clicked)
        self.ledTop.editingFinished.connect(self._log_clicked)
        self.diaRad_Hf.valueChanged.connect(self.draw)
        self.but_fir_poles.clicked.connect(self.draw)

    # --------------------------------------------------------------------------
    def _log_clicked(self):
        """
        Change scale and settings to log / lin when log setting is changed
        Update min / max settings when lineEdits have been edited
        """
        # clicking but_log triggered the slot or initialization
        if self.sender() is None or self.sender().objectName() == 'but_log':
            if self.but_log.isChecked():
                self.ledBottom.setText(str(self.zmin_dB))
                self.zmax_dB = np.round(20 * np.log10(self.zmax), 2)
                self.ledTop.setText(str(self.zmax_dB))
            else:
                self.ledBottom.setText(str(self.zmin))
                self.zmax = np.round(10**(self.zmax_dB / 20), 2)
                self.ledTop.setText(str(self.zmax))

        else:  # finishing a lineEdit field triggered the slot
            if self.but_log.isChecked():
                self.zmin_dB = safe_eval(
                    self.ledBottom.text(), self.zmin_dB, return_type='float')
                self.ledBottom.setText(str(self.zmin_dB))
                self.zmax_dB = safe_eval(
                    self.ledTop.text(), self.zmax_dB, return_type='float')
                self.ledTop.setText(str(self.zmax_dB))
            else:
                self.zmin = safe_eval(
                    self.ledBottom.text(), self.zmin, return_type='float')
                self.ledBottom.setText(str(self.zmin))
                self.zmax = safe_eval(self.ledTop.text(), self.zmax, return_type='float')
                self.ledTop.setText(str(self.zmax))

        self.draw()

    # --------------------------------------------------------------------------
    def init_axes(self):
        """
        Initialize and clear the axes (this is only run once)
        """
        self.mplwidget.fig.clf()  # needed to get rid of colorbar
        if len(self.mplwidget.fig.get_axes()) == 0:  # empty figure, no axes
            self.ax = self.mplwidget.fig.subplots()  # .add_subplot(111)
        self.ax.xaxis.tick_bottom()  # remove axis ticks on top
        self.ax.yaxis.tick_left()  # remove axis ticks right

    # --------------------------------------------------------------------------
    def update_view(self):
        """
        Draw the figure with new limits, scale etcs without recalculating H(f)
        -- not yet implemented, just use draw() for the moment
        """
        self.draw()

    # --------------------------------------------------------------------------
    def draw(self):
        self.but_fir_poles.setVisible(fb.fil[0]['ft'] == 'FIR')
        contour = qget_cmb_box(self.cmb_overlay) in {"contour", "contourf"}
        self.ledBottom.setVisible(contour)
        self.lblBottom.setVisible(contour)
        self.lblBottomdB.setVisible(contour and self.but_log.isChecked())
        self.ledTop.setVisible(contour)
        self.lblTop.setVisible(contour)
        self.lblTopdB.setVisible(contour and self.but_log.isChecked())

        if True:
            self.init_axes()
        self.draw_pz()

    # --------------------------------------------------------------------------
    def draw_pz(self):
        """
        (re)draw P/Z plot
        """
        p_marker = params['P_Marker']
        z_marker = params['Z_Marker']

        zpk = fb.fil[0]['zpk']

        # add antiCausals if they exist (must take reciprocal to plot)
        if 'rpk' in fb.fil[0]:
            zA = fb.fil[0]['zpk'][0]
            zA = np.conj(1./zA)
            pA = fb.fil[0]['zpk'][1]
            pA = np.conj(1./pA)
            zC = np.append(zpk[0], zA)
            pC = np.append(zpk[1], pA)
            zpk[0] = zC
            zpk[1] = pC

        self.ax.clear()

        [z, p, k] = self.zplane(
            z=zpk[0], p=zpk[1], k=zpk[2], plt_ax=self.ax,
            plt_poles=self.but_fir_poles.isChecked() or fb.fil[0]['ft'] == 'IIR',
            mps=p_marker[0], mpc=p_marker[1], mzs=z_marker[0], mzc=z_marker[1])

        self.ax.xaxis.set_minor_locator(AutoMinorLocator())  # enable minor ticks
        self.ax.yaxis.set_minor_locator(AutoMinorLocator())  # enable minor ticks
        self.ax.set_title(r'Pole / Zero Plot')
        self.ax.set_xlabel('Real axis')
        self.ax.set_ylabel('Imaginary axis')

        overlay = qget_cmb_box(self.cmb_overlay)
        self.but_log.setVisible(overlay != "none")

        self.draw_Hf(r=self.diaRad_Hf.value(), Hf_visible=(overlay == "h(f)"))

        self.draw_contours(overlay)

        self.redraw()

    # --------------------------------------------------------------------------
    def redraw(self):
        """
        Redraw the canvas when e.g. the canvas size has changed
        """
        self.mplwidget.redraw()

    # --------------------------------------------------------------------------
    def zplane(self, b=None, a=1, z=None, p=None, k=1,  pn_eps=1e-3, analog=False,
               plt_ax=None, plt_poles=True, style='equal', anaCircleRad=0, lw=2,
               mps=10, mzs=10, mpc='r', mzc='b', plabel='', zlabel=''):
        """
        Plot the poles and zeros in the complex z-plane either from the
        coefficients (`b,`a) of a discrete transfer function `H`(`z`) (zpk = False)
        or directly from the zeros and poles (z,p) (zpk = True).

        When only b is given, an FIR filter with all poles at the origin is assumed.

        Parameters
        ----------
        b :  array_like
             Numerator coefficients (transversal part of filter)
             When b is not None, poles and zeros are determined from the coefficients
             b and a

        a :  array_like (optional, default = 1 for FIR-filter)
             Denominator coefficients (recursive part of filter)

        z :  array_like, default = None
             Zeros
             When b is None, poles and zeros are taken directly from z and p

        p :  array_like, default = None
             Poles

        analog : boolean (default: False)
            When True, create a P/Z plot suitable for the s-plane, i.e. suppress
            the unit circle (unless anaCircleRad > 0) and scale the plot for
            a good display of all poles and zeros.

        pn_eps : float (default : 1e-2)
             Tolerance for separating close poles or zeros

        plt_ax : handle to axes for plotting (default: None)
            When no axes is specified, the current axes is determined via plt.gca()

        plt_poles : Boolean (default : True)
            Plot poles. This can be used to suppress poles for FIR systems
            where all poles are at the origin.

        style : string (default: 'scaled')
            Style of the plot, for `style == 'scaled'` make scale of x- and y-
            axis equal, `style == 'equal'` forces x- and y-axes to be equal. This
            is passed as an argument to the matplotlib `ax.axis(style)`

        mps : integer  (default: 10)
            Size for pole marker

        mzs : integer (default: 10)
            Size for zero marker

        mpc : char (default: 'r')
            Pole marker colour

        mzc : char (default: 'b')
            Zero marker colour

        lw : integer (default:  2)
            Linewidth for unit circle

        plabel, zlabel : string (default: '')
            This string is passed to the plot command for poles and zeros and
            can be displayed by legend()


        Returns
        -------
        z, p, k : ndarray


        Notes
        -----
        """
        # TODO:
        # - polar option
        # - add keywords for color of circle -> **kwargs
        # - add option for multi-dimensional arrays and zpk data

        # make sure that all inputs are (at least 1D) arrays
        b = np.atleast_1d(b)
        a = np.atleast_1d(a)
        z = np.atleast_1d(z)
        p = np.atleast_1d(p)

        if b.any():  # coefficients were specified
            if len(b) < 2 and len(a) < 2:
                logger.error('No proper filter coefficients: both b and a are scalars!')
                return z, p, k

            # The coefficients are less than 1, normalize the coefficients
            if np.max(b) > 1:
                kn = np.max(b)
                b = b / float(kn)
            else:
                kn = 1.

            if np.max(a) > 1:
                kd = np.max(a)
                a = a / abs(kd)
            else:
                kd = 1.

            # Calculate the poles, zeros and scaling factor
            p = np.roots(a)
            z = np.roots(b)
            k = kn/kd
        elif not (len(p) or len(z)):  # P/Z were specified
            logger.error('Either b,a or z,p must be specified!')
            return z, p, k

        # find multiple poles and zeros and their multiplicities
        if len(p) < 2:  # single pole, [None] or [0]
            if not p or p == 0:  # only zeros, create equal number of poles at origin
                p = np.array(0, ndmin=1)
                num_p = np.atleast_1d(len(z))
            else:
                num_p = [1.]  # single pole != 0
        else:
            # p, num_p = sig.signaltools.unique_roots(p, tol = pn_eps, rtype='avg')
            p, num_p = unique_roots(p, tol=pn_eps, rtype='avg')
    #        p = np.array(p); num_p = np.ones(len(p))
        if len(z) > 0:
            z, num_z = unique_roots(z, tol=pn_eps, rtype='avg')
    #        z = np.array(z); num_z = np.ones(len(z))
            # z, num_z = sig.signaltools.unique_roots(z, tol = pn_eps, rtype='avg')
        else:
            num_z = []

        if analog is False:
            # create the unit circle for the z-plane
            uc = patches.Circle((0, 0), radius=1, fill=False,
                                color='grey', ls='solid', zorder=1)
            plt_ax.add_patch(uc)
            plt_ax.axis(style)
        #    ax.spines['left'].set_position('center')
        #    ax.spines['bottom'].set_position('center')
        #    ax.spines['right'].set_visible(True)
        #    ax.spines['top'].set_visible(True)

        else:  # s-plane
            if anaCircleRad > 0:
                # plot a circle with radius = anaCircleRad
                uc = patches.Circle((0, 0), radius=anaCircleRad, fill=False,
                                    color='grey', ls='solid', zorder=1)
                plt_ax.add_patch(uc)
            # plot real and imaginary axis
            plt_ax.axhline(lw=2, color='k', zorder=1)
            plt_ax.axvline(lw=2, color='k', zorder=1)

        # Plot the zeros
        plt_ax.scatter(z.real, z.imag, s=mzs*mzs, zorder=2, marker='o',
                       facecolor='none', edgecolor=mzc, lw=lw, label=zlabel)
        # and print their multiplicity
        for i in range(len(z)):
            logger.debug('z: {0} | {1} | {2}'.format(i, z[i], num_z[i]))
            if num_z[i] > 1:
                plt_ax.text(np.real(z[i]), np.imag(z[i]), '  (' + str(num_z[i]) + ')',
                            va='top', color=mzc)
        if plt_poles:
            # Plot the poles
            plt_ax.scatter(p.real, p.imag, s=mps*mps, zorder=2, marker='x',
                           color=mpc, lw=lw, label=plabel)
            # and print their multiplicity
            for i in range(len(p)):
                logger.debug('p:{0} | {1} | {2}'.format(i, p[i], num_p[i]))
                if num_p[i] > 1:
                    plt_ax.text(np.real(p[i]), np.imag(p[i]), '  (' + str(num_p[i]) + ')',
                                va='bottom', color=mpc)

# =============================================================================
#            # increase distance between ticks and labels
#            # to give some room for poles and zeros
#         for tick in ax.get_xaxis().get_major_ticks():
#             tick.set_pad(12.)
#             tick.label1 = tick._get_text1()
#         for tick in ax.get_yaxis().get_major_ticks():
#             tick.set_pad(12.)
#             tick.label1 = tick._get_text1()
#
# =============================================================================
        xl = plt_ax.get_xlim()
        Dx = max(abs(xl[1]-xl[0]), 0.05)
        yl = plt_ax.get_ylim()
        Dy = max(abs(yl[1]-yl[0]), 0.05)

        plt_ax.set_xlim((xl[0]-Dx*0.02, max(xl[1]+Dx*0.02, 0)))
        plt_ax.set_ylim((yl[0]-Dy*0.02, yl[1] + Dy*0.02))

        return z, p, k

    # --------------------------------------------------------------------------
    def draw_contours(self, overlay):
        if overlay not in {"contour", "contourf"}:
            return
        self.ax.apply_aspect()  # normally, the correct aspect is only set when plotting
        xl = self.ax.get_xlim()
        yl = self.ax.get_ylim()
        # logger.warning(xl)
        # logger.warning(yl)

        [x, y] = np.meshgrid(
            np.arange(xl[0], xl[1], 0.01),
            np.arange(yl[0], yl[1], 0.01))
        z = x + 1j*y  # create coordinate grid for complex plane

        if self.but_log.isChecked():
            H_max = self.zmax_dB
            H_min = self.zmin_dB
        else:
            H_max = self.zmax
            H_min = self.zmin
        Hmag = H_mag(fb.fil[0]['ba'][0], fb.fil[0]['ba'][1], z, H_max, H_min=H_min,
                     log=self.but_log.isChecked())

        if overlay == "contour":
            self.ax.contour(x, y, Hmag, 20, alpha=0.5, cmap=self.cmap)
        else:
            self.ax.contourf(x, y, Hmag, 20, alpha=0.5, cmap=self.cmap)

        m_cb = cm.ScalarMappable(cmap=self.cmap)    # normalized proxy object that is
        m_cb.set_array(Hmag)                        # mappable for colorbar (?)
        self.col_bar = self.mplwidget.fig.colorbar(
            m_cb, ax=self.ax, shrink=1.0, aspect=40, pad=0.01, fraction=0.08)

        # Contour plots and color bar somehow mess up the coordinates:
        # restore to previous settings
        self.ax.set_xlim(xl)
        self.ax.set_xlim(yl)

    # --------------------------------------------------------------------------
    def draw_Hf(self, r=2, Hf_visible=True):
        """
        Draw the magnitude frequency response around the UC
        """
        self.diaRad_Hf.setVisible(Hf_visible)
        self.lblRad_Hf.setVisible(Hf_visible)
        if not Hf_visible:
            return

        # suppress "divide by zero in log10" warnings
        old_settings_seterr = np.seterr()
        np.seterr(divide='ignore')
        ba = fb.fil[0]['ba']
        w, H = sig.freqz(ba[0], ba[1], worN=params['N_FFT'], whole=True)
        H = np.abs(H)
        if self.but_log.isChecked():
            H = np.clip(np.log10(H), -6, None)  # clip to -120 dB
            H = H - np.max(H)  # shift scale to H_min ... 0
            H = 1 + (r-1) * (1 + H / abs(np.min(H)))  # scale to 1 ... r
        else:
            H = 1 + (r-1) * H / np.max(H)  # map |H(f)| to a range 1 ... r
        y = H * np.sin(w)
        x = H * np.cos(w)

        self.ax.plot(x, y, label="|H(f)|")
        uc = patches.Circle((0, 0), radius=r, fill=False,
                            color='grey', ls='dashed', zorder=1)
        self.ax.add_patch(uc)

        xl = self.ax.get_xlim()
        xmax = max(abs(xl[0]), abs(xl[1]), r*1.05)
        yl = self.ax.get_ylim()
        ymax = max(abs(yl[0]), abs(yl[1]), r*1.05)
        self.ax.set_xlim((-xmax, xmax))
        self.ax.set_ylim((-ymax, ymax))

        np.seterr(**old_settings_seterr)