pyqtgraph/examples/PlotSpeedTest.py

53 lines
1.2 KiB
Python

#!/usr/bin/python
# -*- coding: utf-8 -*-
"""
Update a simple plot as rapidly as possible to measure speed.
"""
## Add path to library (just for examples; you do not need this)
import initExample
from pyqtgraph.Qt import QtGui, QtCore
import numpy as np
import pyqtgraph as pg
from pyqtgraph.ptime import time
app = pg.mkQApp("Plot Speed Test")
p = pg.plot()
p.setWindowTitle('pyqtgraph example: PlotSpeedTest')
p.setRange(QtCore.QRectF(0, -10, 5000, 20))
p.setLabel('bottom', 'Index', units='B')
curve = p.plot()
#curve.setFillBrush((0, 0, 100, 100))
#curve.setFillLevel(0)
#lr = pg.LinearRegionItem([100, 4900])
#p.addItem(lr)
data = np.random.normal(size=(50,5000))
ptr = 0
lastTime = time()
fps = None
def update():
global curve, data, ptr, p, lastTime, fps
curve.setData(data[ptr%10])
ptr += 1
now = time()
dt = now - lastTime
lastTime = now
if fps is None:
fps = 1.0/dt
else:
s = np.clip(dt*3., 0, 1)
fps = fps * (1-s) + (1.0/dt) * s
p.setTitle('%0.2f fps' % fps)
app.processEvents() ## force complete redraw for every plot
timer = QtCore.QTimer()
timer.timeout.connect(update)
timer.start(0)
if __name__ == '__main__':
pg.mkQApp().exec_()