Beispiel #1
0
    def _construct_UI(self):
        """
        Intitialize the user interface
        -
        """
        # widget / subwindow for parameter selection
        self.butSave = QPushButton("Save Filter", self)
        self.butLoad = QPushButton("Load Filter", self)
        self.butAbout = QPushButton("About", self)

        # ============== UI Layout =====================================
        bfont = QFont()
        bfont.setBold(True)

        bifont = QFont()
        bifont.setBold(True)
        bifont.setItalic(True)

        ifont = QFont()
        ifont.setItalic(True)

        layVIO = QVBoxLayout()
        layVIO.addWidget(self.butSave)  # save filter dict -> various formats
        layVIO.addWidget(self.butLoad)  # load filter dict -> various formats
        layVIO.addWidget(self.butAbout)  # pop-up "About" window

        # This is the top level widget, encompassing the other widgets
        frmMain = QFrame(self)
        frmMain.setLayout(layVIO)

        layVMain = QVBoxLayout()
        layVMain.setAlignment(Qt.AlignTop)
        #        layVMain.addLayout(layVIO)
        layVMain.addWidget(frmMain)
        layVMain.setContentsMargins(*params['wdg_margins'])

        self.setLayout(layVMain)

        #----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        #----------------------------------------------------------------------
        self.butSave.clicked.connect(self.save_filter)
        self.butLoad.clicked.connect(self.load_filter)
        self.butAbout.clicked.connect(self.about_window)
Beispiel #2
0
class Input_Coeffs_UI(QWidget):
    """
    Create the UI for the FilterCoeffs class
    """
    sig_rx = pyqtSignal(dict)  # incoming
    sig_tx = pyqtSignal(dict)  # outgoing
    from pyfda.libs.pyfda_qt_lib import emit

    def __init__(self, parent=None):
        super(Input_Coeffs_UI, self).__init__(parent)
        self.eps = 1.e-6  # initialize tolerance value
        self._construct_UI()

# ------------------------------------------------------------------------------
    def process_sig_rx(self, dict_sig=None):
        """
        Process signals coming from the CSV pop-up window
        """
        # logger.debug("PROCESS_SIG_RX:\n{0}".format(pprint_log(dict_sig)))

        if 'closeEvent' in dict_sig:
            self._close_csv_win()
            self.emit({'ui_changed': 'csv'})
            return
        elif 'ui_changed' in dict_sig:
            self._set_load_save_icons()  # update icons file <-> clipboard
            # inform e.g. the p/z input widget about changes in CSV options
            self.emit({'ui_changed': 'csv'})

# ------------------------------------------------------------------------------
    def _construct_UI(self):
        """
        Intitialize the widget, consisting of:
        - top chkbox row
        - coefficient table
        - two bottom rows with action buttons
        """
        self.bfont = QFont()
        self.bfont.setBold(True)
        self.bifont = QFont()
        self.bifont.setBold(True)
        self.bifont.setItalic(True)
#        q_icon_size = QSize(20, 20) # optional, size is derived from butEnable

        #######################################################################
        # frmMain
        #
        # This frame contains all the buttons
        #######################################################################
        # ---------------------------------------------
        # layHDisplay
        #
        # UI Elements for controlling the display
        # ---------------------------------------------
        self.butEnable = PushButton(self, icon=QIcon(':/circle-check.svg'), checked=True)
        q_icon_size = self.butEnable.iconSize()  # <- uncomment this for manual sizing
        self.butEnable.setToolTip(
            "<span>Show / hide filter coefficients in an editable table."
            " For high order systems, table display might be slow.</span>")

        fix_formats = ['Dec', 'Hex', 'Bin', 'CSD']
        self.cmbFormat = QComboBox(self)
        model = self.cmbFormat.model()
        item = QtGui.QStandardItem('Float')
        item.setData('child', Qt.AccessibleDescriptionRole)
        model.appendRow(item)

        item = QtGui.QStandardItem('Fixp.:')
        item.setData('parent', Qt.AccessibleDescriptionRole)
        item.setData(0, QtGui.QFont.Bold)
        item.setFlags(item.flags() & ~Qt.ItemIsEnabled)  # | Qt.ItemIsSelectable))
        model.appendRow(item)

        for idx in range(len(fix_formats)):
            item = QtGui.QStandardItem(fix_formats[idx])
#            item.setForeground(QtGui.QColor('red'))
            model.appendRow(item)

        self.cmbFormat.insertSeparator(1)
        qset_cmb_box(self.cmbFormat, 'float')
        self.cmbFormat.setToolTip('Set the display format.')
        self.cmbFormat.setSizeAdjustPolicy(QComboBox.AdjustToContents)

        self.spnDigits = QSpinBox(self)
        self.spnDigits.setRange(0, 16)
        self.spnDigits.setValue(params['FMT_ba'])
        self.spnDigits.setToolTip("Number of digits to display.")
        self.lblDigits = QLabel("Digits", self)
        self.lblDigits.setFont(self.bifont)

        self.cmbQFrmt = QComboBox(self)
        q_formats = [('Norm. Frac.', 'qnfrac'), ('Integer', 'qint'),
                     ('Fractional', 'qfrac')]
        for q in q_formats:
            self.cmbQFrmt.addItem(*q)

        self.lbl_W = QLabel("W = ", self)
        self.lbl_W.setFont(self.bifont)

        self.ledW = QLineEdit(self)
        self.ledW.setToolTip("Specify total wordlength.")
        self.ledW.setText("16")
        self.ledW.setMaxLength(2)  # maximum of 2 digits
        self.ledW.setFixedWidth(30)  # width of lineedit in points(?)

        layHDisplay = QHBoxLayout()
        layHDisplay.setAlignment(Qt.AlignLeft)
        layHDisplay.addWidget(self.butEnable)
        layHDisplay.addWidget(self.cmbFormat)
        layHDisplay.addWidget(self.spnDigits)
        layHDisplay.addWidget(self.lblDigits)
        layHDisplay.addWidget(self.cmbQFrmt)
        layHDisplay.addWidget(self.lbl_W)
        layHDisplay.addWidget(self.ledW)
        layHDisplay.addStretch()

        #######################################################################
        # frmButtonsCoeffs
        #
        # This frame contains all buttons for manipulating coefficients
        #######################################################################
        # -----------------------------------------------------------------
        # layHButtonsCoeffs1
        #
        # UI Elements for loading / storing / manipulating cells and rows
        # -----------------------------------------------------------------
        self.cmbFilterType = QComboBox(self)
        self.cmbFilterType.setObjectName("comboFilterType")
        self.cmbFilterType.setToolTip(
            "<span>Select between IIR and FIR filter for manual entry."
            "Changing the type reloads the filter from the filter dict.</span>")
        self.cmbFilterType.addItems(["FIR", "IIR"])
        self.cmbFilterType.setSizeAdjustPolicy(QComboBox.AdjustToContents)

        self.butAddCells = QPushButton(self)
        self.butAddCells.setIcon(QIcon(':/row_insert_above.svg'))
        self.butAddCells.setIconSize(q_icon_size)
        self.butAddCells.setToolTip(
            "<span>Select cells to insert a new cell above each selected cell. "
            "Use &lt;SHIFT&gt; or &lt;CTRL&gt; to select multiple cells. "
            "When nothing is selected, add a row at the end.</span>")

        self.butDelCells = QPushButton(self)
        self.butDelCells.setIcon(QIcon(':/row_delete.svg'))
        self.butDelCells.setIconSize(q_icon_size)
        self.butDelCells.setToolTip(
            "<span>Delete selected cell(s) from the table. "
            "Use &lt;SHIFT&gt; or &lt;CTRL&gt; to select multiple cells. "
            "When nothing is selected, delete the last row.</span>")

        self.butSave = QPushButton(self)
        self.butSave.setIcon(QIcon(':/upload.svg'))
        self.butSave.setIconSize(q_icon_size)
        self.butSave.setToolTip(
            "<span>Copy coefficient table to filter dict and update all plots"
            "and widgets.</span>")

        self.butLoad = QPushButton(self)
        self.butLoad.setIcon(QIcon(':/download.svg'))
        self.butLoad.setIconSize(q_icon_size)
        self.butLoad.setToolTip("Reload coefficient table from filter dict.")

        self.butClear = QPushButton(self)
        self.butClear.setIcon(QIcon(':/trash.svg'))
        self.butClear.setIconSize(q_icon_size)
        self.butClear.setToolTip("Clear all table entries.")

        self.butFromTable = QPushButton(self)
        self.butFromTable.setIconSize(q_icon_size)

        self.butToTable = QPushButton(self)
        self.butToTable.setIconSize(q_icon_size)

        self.but_csv_options = PushButton(self, icon=QIcon(':/settings.svg'),
                                          checked=False)
        self.but_csv_options.setIconSize(q_icon_size)
        self.but_csv_options.setToolTip(
            "<span>Select CSV format and whether "
            "to copy to/from clipboard or file.</span>")

        self._set_load_save_icons()  # initialize icon / button settings

        layHButtonsCoeffs1 = QHBoxLayout()
        layHButtonsCoeffs1.addWidget(self.cmbFilterType)
        layHButtonsCoeffs1.addWidget(self.butAddCells)
        layHButtonsCoeffs1.addWidget(self.butDelCells)
        layHButtonsCoeffs1.addWidget(self.butClear)
        layHButtonsCoeffs1.addWidget(self.butSave)
        layHButtonsCoeffs1.addWidget(self.butLoad)
        layHButtonsCoeffs1.addWidget(self.butFromTable)
        layHButtonsCoeffs1.addWidget(self.butToTable)
        layHButtonsCoeffs1.addWidget(self.but_csv_options)
        layHButtonsCoeffs1.addStretch()

        # ----------------------------------------------------------------------
        # layHButtonsCoeffs2
        #
        # Eps / set zero settings
        # ---------------------------------------------------------------------
        self.butSetZero = QPushButton("= 0", self)
        self.butSetZero.setToolTip(
            "<span>Set selected coefficients = 0 with a magnitude &lt; &epsilon;. "
            "When nothing is selected, test the whole table.</span>")
        self.butSetZero.setIconSize(q_icon_size)

        lblEps = QLabel(self)
        lblEps.setText("<b><i>for b, a</i> &lt;</b>")

        self.ledEps = QLineEdit(self)
        self.ledEps.setToolTip("Specify tolerance value.")

        layHButtonsCoeffs2 = QHBoxLayout()
        layHButtonsCoeffs2.addWidget(self.butSetZero)
        layHButtonsCoeffs2.addWidget(lblEps)
        layHButtonsCoeffs2.addWidget(self.ledEps)
        layHButtonsCoeffs2.addStretch()

        # -------------------------------------------------------------------
        # Now put the ButtonsCoeffs HBoxes into frmButtonsCoeffs
        # ---------------------------------------------------------------------
        layVButtonsCoeffs = QVBoxLayout()
        layVButtonsCoeffs.addLayout(layHButtonsCoeffs1)
        layVButtonsCoeffs.addLayout(layHButtonsCoeffs2)
        layVButtonsCoeffs.setContentsMargins(0, 5, 0, 0)
        # This frame encompasses all Quantization Settings
        self.frmButtonsCoeffs = QFrame(self)
        self.frmButtonsCoeffs.setLayout(layVButtonsCoeffs)

        # ######################################################################
        # frmQSettings
        #
        # This frame contains all quantization settings
        # ######################################################################
        # -------------------------------------------------------------------
        # layHW_Scale
        #
        # QFormat and scale settings
        # ---------------------------------------------------------------------
        lbl_Q = QLabel("Q =", self)
        lbl_Q.setFont(self.bifont)

        self.ledWI = QLineEdit(self)
        self.ledWI.setToolTip("Specify number of integer bits.")
        self.ledWI.setText("0")
        self.ledWI.setMaxLength(2)  # maximum of 2 digits
        self.ledWI.setFixedWidth(30)  # width of lineedit in points(?)

        self.lblDot = QLabel(".", self)  # class attribute, visibility is toggled
        self.lblDot.setFont(self.bfont)

        self.ledWF = QLineEdit(self)
        self.ledWF.setToolTip("Specify number of fractional bits.")
        self.ledWF.setText("15")
        self.ledWF.setMaxLength(2)  # maximum of 2 digits
#        self.ledWF.setFixedWidth(30) # width of lineedit in points(?)
        self.ledWF.setMaximumWidth(30)

        self.lblScale = QLabel("<b><i>Scale</i> =</b>", self)
        self.ledScale = QLineEdit(self)
        self.ledScale.setToolTip(
            "Set the scale for converting float to fixpoint representation.")
        self.ledScale.setText(str(1))
        self.ledScale.setEnabled(False)

        layHWI_WF = QHBoxLayout()
        layHWI_WF.addWidget(lbl_Q)
        layHWI_WF.addWidget(self.ledWI)
        layHWI_WF.addWidget(self.lblDot)
        layHWI_WF.addWidget(self.ledWF)
        layHWI_WF.addStretch()

        layHScale = QHBoxLayout()
        layHScale.addWidget(self.lblScale)
        layHScale.addWidget(self.ledScale)
        layHScale.addStretch()

        layHW_Scale = QHBoxLayout()
        layHW_Scale.addLayout(layHWI_WF)
        layHW_Scale.addLayout(layHScale)

        # -------------------------------------------------------------------
        # layGQOpt
        #
        # Quantization / Overflow / MSB / LSB settings
        # ---------------------------------------------------------------------
        lblQOvfl = QLabel("Ovfl.:", self)
        lblQOvfl.setFont(self.bifont)
        lblQuant = QLabel("Quant.:", self)
        lblQuant.setFont(self.bifont)

        self.cmbQOvfl = QComboBox(self)
        qOvfl = ['wrap', 'sat']
        self.cmbQOvfl.addItems(qOvfl)
        qset_cmb_box(self.cmbQOvfl, 'sat')
        self.cmbQOvfl.setToolTip("Select overflow behaviour.")
        # ComboBox size is adjusted automatically to fit the longest element
        self.cmbQOvfl.setSizeAdjustPolicy(QComboBox.AdjustToContents)

        layHQOvflOpt = QHBoxLayout()
        layHQOvflOpt.addWidget(lblQOvfl)
        layHQOvflOpt.addWidget(self.cmbQOvfl)
        layHQOvflOpt.addStretch()

        self.cmbQuant = QComboBox(self)
        qQuant = ['none', 'round', 'fix', 'floor']
        self.cmbQuant.addItems(qQuant)
        qset_cmb_box(self.cmbQuant, 'round')
        self.cmbQuant.setToolTip("Select the kind of quantization.")
        self.cmbQuant.setSizeAdjustPolicy(QComboBox.AdjustToContents)

        layHQuantOpt = QHBoxLayout()
        layHQuantOpt.addWidget(lblQuant)
        layHQuantOpt.addWidget(self.cmbQuant)
        layHQuantOpt.addStretch()

        self.butQuant = QPushButton(self)
        self.butQuant.setToolTip(
            "<span>Quantize selected coefficients / "
            "whole table with specified settings.</span>")
        self.butQuant.setIcon(QIcon(':/quantize.svg'))
        self.butQuant.setIconSize(q_icon_size)
        self.butQuant.setSizePolicy(QSizePolicy.Fixed, QSizePolicy.Fixed)

        lblMSBtxt = QLabel(self)
        lblMSBtxt.setText("<b><i>MSB</i><sub>10</sub> =</b>")
        self.lblMSB = QLabel(self)
        layHMSB = QHBoxLayout()
        layHMSB.addWidget(lblMSBtxt)
        layHMSB.addWidget(self.lblMSB)
        layHMSB.addStretch()

        lblLSBtxt = QLabel(self)
        lblLSBtxt.setText("<b><i>LSB</i><sub>10</sub> =</b>")
        self.lblLSB = QLabel(self)
        layHLSB = QHBoxLayout()
        layHLSB.addWidget(lblLSBtxt)
        layHLSB.addWidget(self.lblLSB)
        layHLSB.addStretch()

        layGQOpt = QGridLayout()
        layGQOpt.addLayout(layHQOvflOpt, 0, 0)
        layGQOpt.addLayout(layHQuantOpt, 0, 1)
        layGQOpt.addWidget(self.butQuant, 0, 2, Qt.AlignCenter)
        layGQOpt.addLayout(layHMSB, 1, 0)
        layGQOpt.addLayout(layHLSB, 1, 1)

        # -------------------------------------------------------------------
        #   Display MAX
        # ---------------------------------------------------------------------
        lblMAXtxt = QLabel(self)
        lblMAXtxt.setText("<b><i>Max =</i></b>")
        self.lblMAX = QLabel(self)

        layHCoeffs_MAX = QHBoxLayout()
        layHCoeffs_MAX.addWidget(lblMAXtxt)
        layHCoeffs_MAX.addWidget(self.lblMAX)
        layHCoeffs_MAX.addStretch()

        #######################################################################
        # Now put all the coefficient HBoxes into frmQSettings
        # ---------------------------------------------------------------------
        layVButtonsQ = QVBoxLayout()
        layVButtonsQ.addLayout(layHW_Scale)
        layVButtonsQ.addLayout(layGQOpt)
        layVButtonsQ.addLayout(layHCoeffs_MAX)
        layVButtonsQ.setContentsMargins(0, 0, 0, 0)
        # This frame encompasses all Quantization Settings
        self.frmQSettings = QFrame(self)
        self.frmQSettings.setLayout(layVButtonsQ)

        #######################################################################
        # ########################  Main UI Layout ############################
        #######################################################################
        # layout for frame (UI widget)
        layVMainF = QVBoxLayout()
        layVMainF.addLayout(layHDisplay)
        layVMainF.addWidget(self.frmQSettings)
        layVMainF.addWidget(QHLine())
        layVMainF.addWidget(self.frmButtonsCoeffs)

        # This frame encompasses all UI elements
        frmMain = QFrame(self)
        frmMain.setLayout(layVMainF)

        layVMain = QVBoxLayout()
        # the following affects only the first widget (intended here)
        layVMain.setAlignment(Qt.AlignTop)
        layVMain.addWidget(frmMain)
        layVMain.setContentsMargins(*params['wdg_margins'])
        self.setLayout(layVMain)
        #######################################################################

        # --- set initial values from dict ------------
        self.spnDigits.setValue(params['FMT_ba'])
        self.ledEps.setText(str(self.eps))

        # ----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        # ----------------------------------------------------------------------
        self.but_csv_options.clicked.connect(self._open_csv_win)

    # --------------------------------------------------------------------------
    def _open_csv_win(self):
        """
        Pop-up window for CSV options
        """
        if self.but_csv_options.isChecked():
            qstyle_widget(self.but_csv_options, "changed")
        else:
            qstyle_widget(self.but_csv_options, "normal")

        if dirs.csv_options_handle is None:
            # no handle to the window? Create a new instance
            if self.but_csv_options.isChecked():
                # Important: Handle to window must be class attribute, otherwise it
                # (and the attached window) is deleted immediately when it goes
                # out of scope
                dirs.csv_options_handle = CSV_option_box(self)
                dirs.csv_options_handle.sig_tx.connect(self.process_sig_rx)
                dirs.csv_options_handle.show()  # modeless i.e. non-blocking popup window
        else:
            if not self.but_csv_options.isChecked():  # this should not happen
                if dirs.csv_options_handle is None:
                    logger.warning("CSV options window is already closed!")
                else:
                    dirs.csv_options_handle.close()

        self.emit({'ui_changed': 'csv'})

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

    def _close_csv_win(self):
        dirs.csv_options_handle = None
        self.but_csv_options.setChecked(False)
        qstyle_widget(self.but_csv_options, "normal")

    # ------------------------------------------------------------------------------
    def _set_load_save_icons(self):
        """
        Set icons / tooltipps for loading and saving data to / from file or
        clipboard depending on selected options.
        """
        if params['CSV']['clipboard']:
            self.butFromTable.setIcon(QIcon(':/to_clipboard.svg'))
            self.butFromTable.setToolTip(
                "<span>Copy table to clipboard, SELECTED items are copied as "
                "displayed. When nothing is selected, the whole table "
                "is copied with full precision in decimal format.</span>")

            self.butToTable.setIcon(QIcon(':/from_clipboard.svg'))
            self.butToTable.setToolTip("<span>Copy clipboard to table.</span>")
        else:
            self.butFromTable.setIcon(QIcon(':/save.svg'))
            self.butFromTable.setToolTip(
                "<span>"
                "Save table to file, SELECTED items are copied as "
                "displayed. When nothing is selected, the whole table "
                "is copied with full precision in decimal format.</span>")

            self.butToTable.setIcon(QIcon(':/file.svg'))
            self.butToTable.setToolTip("<span>Load table from file.</span>")

        if dirs.csv_options_handle is None:
            qstyle_widget(self.but_csv_options, "normal")
            self.but_csv_options.setChecked(False)
        else:
            qstyle_widget(self.but_csv_options, "changed")
            self.but_csv_options.setChecked(True)
Beispiel #3
0
class Input_PZ_UI(QWidget):
    """
    Create the UI for the FilterPZ class
    """

    sig_rx = pyqtSignal(object) # incoming
    sig_tx = pyqtSignal(object) # outgoing

    def __init__(self, parent):
        """
        Pass instance `parent` of parent class (FilterCoeffs)
        """
        super(Input_PZ_UI, self).__init__(parent)
#        self.parent = parent # instance of the parent (not the base) class
        self.eps = 1.e-4 # # tolerance value for e.g. setting P/Z to zero
        self._construct_UI()

#------------------------------------------------------------------------------
    def process_sig_rx(self, dict_sig=None):
        """
        Process signals coming from the CSV pop-up window
        """

        logger.debug("PROCESS_SIG_RX\n{0}".format(pprint_log(dict_sig)))
        
        if 'closeEvent' in dict_sig:
            self._close_csv_win()
            self.sig_tx.emit({'sender':__name__, 'ui_changed': 'csv'})
            return # probably not needed
        elif 'ui_changed' in dict_sig:
            self._set_load_save_icons() # update icons file <-> clipboard
            # inform e.g. the p/z input widget about changes in CSV options 
            self.sig_tx.emit({'sender':__name__, 'ui_changed': 'csv'})

#------------------------------------------------------------------------------
    def _construct_UI(self):        
        """
        Intitialize the widget, consisting of:
        - top chkbox row
        - coefficient table
        - two bottom rows with action buttons
        """
        
        self.bfont = QFont()
        self.bfont.setBold(True)
        self.bifont = QFont()
        self.bifont.setBold(True)
        self.bifont.setItalic(True)
#        q_icon_size = QSize(20, 20) # optional, size is derived from butEnable

        # ---------------------------------------------
        # UI Elements for controlling the display
        # ---------------------------------------------
        
        self.butEnable = QPushButton(self)
        self.butEnable.setIcon(QIcon(':/circle-x.svg'))
        q_icon_size = self.butEnable.iconSize() # <- set this for manual icon sizing
        self.butEnable.setIconSize(q_icon_size)
        self.butEnable.setCheckable(True)
        self.butEnable.setChecked(True)
        self.butEnable.setToolTip("<span>Show / hide poles and zeros in an editable table."
                " For high order systems, the table display might be slow.</span>")

        self.cmbPZFrmt = QComboBox(self)
        pz_formats = [('Cartesian', 'cartesian'), ('Polar (rad)', 'polar_rad'),
                      ('Polar (pi)', 'polar_pi'), ('Polar (°)', 'polar_deg')] # display text, data
        # π: u'3C0, °: u'B0, ∠: u'2220
        for pz in pz_formats:
            self.cmbPZFrmt.addItem(*pz)
        self.cmbPZFrmt.setSizeAdjustPolicy(QComboBox.AdjustToContents)
        # self.cmbPZFrmt.setEnabled(False)
        self.cmbPZFrmt.setToolTip("<span>Set display format for poles and zeros to"
                                  " either cartesian (x + jy) or polar (r * &ang; &Omega;)."
                                  " Type 'o' for '&deg;', '&lt;' for '&ang;' and 'pi' for '&pi;'.</span>")

        self.spnDigits = QSpinBox(self)
        self.spnDigits.setRange(0,16)
        self.spnDigits.setToolTip("Number of digits to display.")
        self.lblDigits = QLabel("Digits", self)
        self.lblDigits.setFont(self.bifont)
        
        self.cmbCausal = QComboBox(self)
        causal_types = ['Causal', 'Acausal', 'Anticausal']
        for cs in causal_types:
            self.cmbCausal.addItem(cs)

        qset_cmb_box(self.cmbCausal, 'Causal')
        self.cmbCausal.setToolTip('<span>Set the system type. Not implemented yet.</span>')
        self.cmbCausal.setSizeAdjustPolicy(QComboBox.AdjustToContents)
        self.cmbCausal.setEnabled(False)
            
        layHDisplay = QHBoxLayout()
        layHDisplay.setAlignment(Qt.AlignLeft)
        layHDisplay.addWidget(self.butEnable)
        layHDisplay.addWidget(self.cmbPZFrmt)
        layHDisplay.addWidget(self.spnDigits)
        layHDisplay.addWidget(self.lblDigits)
        layHDisplay.addWidget(self.cmbCausal)
        layHDisplay.addStretch()

        # ---------------------------------------------
        # UI Elements for setting the gain
        # ---------------------------------------------
        self.lblNorm = QLabel(to_html("Normalize:", frmt='bi'), self)
        self.cmbNorm = QComboBox(self)
        self.cmbNorm.addItems(["None", "1", "Max"])
        self.cmbNorm.setToolTip("<span>Set the gain <i>k</i> so that H(f)<sub>max</sub> is "
                                "either 1 or the max. of the previous system.</span>")

        self.lblGain = QLabel(to_html("k =", frmt='bi'), self)
        self.ledGain = QLineEdit(self)
        self.ledGain.setToolTip("<span>Specify gain factor <i>k</i>"
                                " (only possible for Normalize = 'None').</span>")
        self.ledGain.setText(str(1.))
        self.ledGain.setObjectName("ledGain")
        
        layHGain = QHBoxLayout()
        layHGain.addWidget(self.lblNorm)
        layHGain.addWidget(self.cmbNorm)
        layHGain.addWidget(self.lblGain)
        layHGain.addWidget(self.ledGain)
        layHGain.addStretch()

        # ---------------------------------------------
        # UI Elements for loading / storing / manipulating cells and rows
        # ---------------------------------------------

#        self.cmbFilterType = QComboBox(self)
#        self.cmbFilterType.setObjectName("comboFilterType")
#        self.cmbFilterType.setToolTip("Select between IIR and FIR filte for manual entry.")
#        self.cmbFilterType.addItems(["FIR","IIR"])
#        self.cmbFilterType.setSizeAdjustPolicy(QComboBox.AdjustToContents)


        self.butAddCells = QPushButton(self)
        self.butAddCells.setIcon(QIcon(':/row_insert_above.svg'))
        self.butAddCells.setIconSize(q_icon_size)
        self.butAddCells.setToolTip("<SPAN>Select cells to insert a new cell above each selected cell. "
                                "Use &lt;SHIFT&gt; or &lt;CTRL&gt; to select multiple cells. "
                                "When nothing is selected, add a row at the end.</SPAN>")

        self.butDelCells = QPushButton(self)
        self.butDelCells.setIcon(QIcon(':/row_delete.svg'))
        self.butDelCells.setIconSize(q_icon_size)
        self.butDelCells.setToolTip("<SPAN>Delete selected cell(s) from the table. "
                "Use &lt;SHIFT&gt; or &lt;CTRL&gt; to select multiple cells. "
                "When nothing is selected, delete the last row.</SPAN>")

        self.butSave = QPushButton(self)
        self.butSave.setIcon(QIcon(':/upload.svg'))
        self.butSave.setIconSize(q_icon_size)
        self.butSave.setToolTip("<span>Copy P/Z table to filter dict and update all plots and widgets.</span>")

        self.butLoad = QPushButton(self)
        self.butLoad.setIcon(QIcon(':/download.svg'))
        self.butLoad.setIconSize(q_icon_size)
        self.butLoad.setToolTip("Reload P/Z table from filter dict.")

        self.butClear = QPushButton(self)
        self.butClear.setIcon(QIcon(':/trash.svg'))
        self.butClear.setIconSize(q_icon_size)
        self.butClear.setToolTip("Clear all table entries.")


        self.butFromTable = QPushButton(self)
        self.butFromTable.setIconSize(q_icon_size)
        
        self.butToTable = QPushButton(self)
        self.butToTable.setIconSize(q_icon_size)

        self.but_csv_options = QPushButton(self)
        self.but_csv_options.setIcon(QIcon(':/settings.svg'))
        self.but_csv_options.setIconSize(q_icon_size)
        self.but_csv_options.setToolTip("<span>Select CSV format and whether "
                                "to copy to/from clipboard or file.</span>")
        self.but_csv_options.setCheckable(True)
        self.but_csv_options.setChecked(False)
        
        self._set_load_save_icons() # initialize icon / button settings

        layHButtonsCoeffs1 = QHBoxLayout()
#        layHButtonsCoeffs1.addWidget(self.cmbFilterType)
        layHButtonsCoeffs1.addWidget(self.butAddCells)
        layHButtonsCoeffs1.addWidget(self.butDelCells)
        layHButtonsCoeffs1.addWidget(self.butClear)
        layHButtonsCoeffs1.addWidget(self.butSave)
        layHButtonsCoeffs1.addWidget(self.butLoad)
        layHButtonsCoeffs1.addWidget(self.butFromTable)
        layHButtonsCoeffs1.addWidget(self.butToTable)
        layHButtonsCoeffs1.addWidget(self.but_csv_options)
        layHButtonsCoeffs1.addStretch()

        #-------------------------------------------------------------------
        #   Eps / set zero settings
        # ---------------------------------------------------------------------
        self.butSetZero = QPushButton("= 0", self)
        self.butSetZero.setToolTip("<span>Set selected poles / zeros = 0 with a magnitude &lt; &epsilon;. "
        "When nothing is selected, test the whole table.</span>")
        self.butSetZero.setIconSize(q_icon_size)

        lblEps = QLabel(self)
        lblEps.setText("<b><i>for &epsilon;</i> &lt;</b>")

        self.ledEps = QLineEdit(self)
        self.ledEps.setToolTip("Specify tolerance value.")

        layHButtonsCoeffs2 = QHBoxLayout()
        layHButtonsCoeffs2.addWidget(self.butSetZero)
        layHButtonsCoeffs2.addWidget(lblEps)
        layHButtonsCoeffs2.addWidget(self.ledEps)
        layHButtonsCoeffs2.addStretch()

        # ########################  Main UI Layout ############################
        # layout for frame (UI widget)
        layVMainF = QVBoxLayout()
        layVMainF.addLayout(layHDisplay)
        layVMainF.addLayout(layHGain)
        layVMainF.addLayout(layHButtonsCoeffs1)
        layVMainF.addLayout(layHButtonsCoeffs2)
        # This frame encompasses all UI elements
        frmMain = QFrame(self)
        frmMain.setLayout(layVMainF)

        layVMain = QVBoxLayout()
        layVMain.setAlignment(Qt.AlignTop) # this affects only the first widget (intended here)
        layVMain.addWidget(frmMain)
        layVMain.setContentsMargins(*params['wdg_margins'])
        self.setLayout(layVMain)
        
        #--- set initial values from dict ------------
        self.spnDigits.setValue(params['FMT_pz'])
        self.ledEps.setText(str(self.eps))
        #----------------------------------------------------------------------
        # LOCAL SIGNALS & SLOTs
        #----------------------------------------------------------------------        
        self.but_csv_options.clicked.connect(self._open_csv_win)
                
    #------------------------------------------------------------------------------
    def _open_csv_win(self):
        """
        Pop-up window for CSV options
        """        
        if self.but_csv_options.isChecked():
            qstyle_widget(self.but_csv_options, "changed")
        else:
            qstyle_widget(self.but_csv_options, "normal")

        if dirs.csv_options_handle is None: # no handle to the window? Create a new instance
            if self.but_csv_options.isChecked():
                # Important: Handle to window must be class attribute otherwise it
                # (and the attached window) is deleted immediately when it goes out of scope
                dirs.csv_options_handle = CSV_option_box(self)
                dirs.csv_options_handle.sig_tx.connect(self.process_sig_rx)
                dirs.csv_options_handle.show() # modeless i.e. non-blocking popup window
        else:
            if not self.but_csv_options.isChecked(): # this should not happen
                if dirs.csv_options_handle is None:
                    logger.warning("CSV options window is already closed!")
                else:
                    dirs.csv_options_handle.close()
                    
        self.sig_tx.emit({'sender':__name__, 'ui_changed': 'csv'})

    #------------------------------------------------------------------------------
    def _close_csv_win(self):
        dirs.csv_options_handle = None
        self.but_csv_options.setChecked(False)
        qstyle_widget(self.but_csv_options, "normal")


        
    #------------------------------------------------------------------------------
    def _set_load_save_icons(self):
        """
        Set icons / tooltipps for loading and saving data to / from file or
        clipboard depending on selected options.
        """
        if params['CSV']['clipboard']:
            self.butFromTable.setIcon(QIcon(':/to_clipboard.svg'))
            self.butFromTable.setToolTip("<span>"
                    "Copy table to clipboard, SELECTED items are copied as "
                    "displayed. When nothing is selected, the whole table "
                    "is copied with full precision in decimal format.</span>")

            self.butToTable.setIcon(QIcon(':/from_clipboard.svg'))
            self.butToTable.setToolTip("<span>Copy clipboard to table.</span>")
        else:
            self.butFromTable.setIcon(QIcon(':/save.svg'))
            self.butFromTable.setToolTip("<span>"
                    "Save table to file, SELECTED items are copied as "
                    "displayed. When nothing is selected, the whole table "
                    "is copied with full precision in decimal format.</span>")

            self.butToTable.setIcon(QIcon(':/file.svg'))
            self.butToTable.setToolTip("<span>Load table from file.</span>")            

        if dirs.csv_options_handle is None:
            qstyle_widget(self.but_csv_options, "normal")
            self.but_csv_options.setChecked(False)
        else:
            qstyle_widget(self.but_csv_options, "changed")
            self.but_csv_options.setChecked(True)