Python Pyqtgraph Plot Tutorial

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Create a plot with PyQtgraph

A simple plot can be created with the module pyqtgraph. Mind you, it’s one of the libraries for plotting, there are others like matplotlib.

We start with importing pyqtgraph and defing the plotting data (x and y). Then we plot the data using pg.plot().

pyqtgraph plot

The example below creates a plot using pyqtgraph.

import pyqtgraph as pg
import pyqtgraph.exporters
import numpy as np


theTitle = "pyqtgraph plot"
y = [2,4,6,8,10,12,14,16,18,20]
x = range(0,10)


plt = pg.plot(x, y, title=theTitle, pen='r')
plt.showGrid(x=True,y=True)


if __name__ == '__main__':
    import sys
    if sys.flags.interactive != 1 or not hasattr(pg.QtCore, 'PYQT_VERSION'):
        pg.QtGui.QApplication.exec_()

We can set additional properties of the chart like the labels, add a legend, the colors.
The output will look like this:

In code its like this:

import pyqtgraph as pg
import pyqtgraph.exporters
import numpy as np


theTitle = "pyqtgraph plot"
y = [2,4,6,8,10,12,14,16,18,20]
y2 = [0,1,2,4,12,14,16,17,14,22]
x = range(0,10)


plt = pg.plot()
plt.showGrid(x=True,y=True)
plt.addLegend()


plt.setLabel('left', 'Value', units='V')
plt.setLabel('bottom', 'Time', units='s')
plt.setXRange(0,10)
plt.setYRange(0,20)
plt.setWindowTitle('pyqtgraph plot')


c1 = plt.plot(x, y, pen='b', symbol='x', symbolPen='b', symbolBrush=0.2, name='red')
c2 = plt.plot(x, y2, pen='r', symbol='o', symbolPen='r', symbolBrush=0.2, name='blue')


if __name__ == '__main__':
    import sys
    if sys.flags.interactive != 1 or not hasattr(pg.QtCore, 'PYQT_VERSION'):
        pg.QtGui.QApplication.exec_()

Download PyQt Examples