def setImage(self, x: np.ndarray, y: np.ndarray, z: np.ndarray) -> None:
"""Set data to be plotted as image.
Clears the plot before creating a new image item that gets places in the
plot and linked to the colorscale.
:param x: x coordinates (as 2D meshgrid)
:param y: y coordinates (as 2D meshgrid)
:param z: data values (as 2D meshgrid)
:return: None
"""
self.clearPlot()
self.img = pg.ImageItem()
self.plot.addItem(self.img)
self.img.setImage(z)
self.img.setRect(QtCore.QRectF(x.min(), y.min(), x.max() - x.min(), y.max() - y.min()))
self.colorbar.setImageItem(self.img)
self.colorbar.rounding = (z.max() - z.min()) * 1e-2
self.colorbar.setLevels((z.min(), z.max()))
def image_test():
app = QtWidgets.QApplication([])
# create data
x = np.linspace(0, 10, 51)
y = np.linspace(-4, 4, 51)
xx, yy = np.meshgrid(x, y, indexing='ij')
zz = np.cos(xx)*np.exp(-(yy-1.)**2)
# layout widget
pgWidget = pg.GraphicsLayoutWidget()
# main plot
imgPlot = pgWidget.addPlot(title='my image', row=0, col=0)
img = pg.ImageItem()
imgPlot.addItem(img)
# histogram and colorbar
hist = pg.HistogramLUTItem()
hist.setImageItem(img)
pgWidget.addItem(hist)
hist.gradient.loadPreset('viridis')
# cut elements
pgWidget2 = pg.GraphicsLayoutWidget()
# plots for x and y cuts
xplot = pgWidget2.addPlot(row=1, col=0)
yplot = pgWidget2.addPlot(row=0, col=0)
xplot.addLegend()
yplot.addLegend()
# add crosshair to main plot
vline = pg.InfiniteLine(angle=90, movable=False, pen='r')
hline = pg.InfiniteLine(angle=0, movable=False, pen='b')
imgPlot.addItem(vline, ignoreBounds=True)
imgPlot.addItem(hline, ignoreBounds=True)
def crossMoved(event):
pos = event[0].scenePos()
if imgPlot.sceneBoundingRect().contains(pos):
origin = imgPlot.vb.mapSceneToView(pos)
vline.setPos(origin.x())
hline.setPos(origin.y())
vidx = np.argmin(np.abs(origin.x()-x))
hidx = np.argmin(np.abs(origin.y()-y))
yplot.clear()
yplot.plot(zz[vidx, :], y, name='vertical cut',
pen=pg.mkPen('r', width=2),
symbol='o', symbolBrush='r', symbolPen=None)
xplot.clear()
xplot.plot(x, zz[:, hidx], name='horizontal cut',
pen=pg.mkPen('b', width=2),
symbol='o', symbolBrush='b', symbolPen=None)
proxy = pg.SignalProxy(imgPlot.scene().sigMouseClicked, slot=crossMoved)
dg = widgetDialog(pgWidget, title='pyqtgraph image test')
dg2 = widgetDialog(pgWidget2, title='line cuts')
# setting the data
img.setImage(zz)
img.setRect(QtCore.QRectF(0, -4, 10, 8.))
hist.setLevels(zz.min(), zz.max())
# formatting
imgPlot.setLabel('left', "Y", units='T')
imgPlot.setLabel('bottom', "X", units='A')
xplot.setLabel('left', 'Z')
xplot.setLabel('bottom', "X", units='A')
yplot.setLabel('left', "Y", units='T')
yplot.setLabel('bottom', "Z")
if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
QtWidgets.QApplication.instance().exec_()