import random
import numpy as np
from qtpy.QtCore import QSize, Qt
from qtpy.QtGui import QBrush, QPen
from qtpy.QtWidgets import QFrame
from qwt import (
QwtAbstractScaleDraw,
QwtLegend,
QwtPlot,
QwtPlotCurve,
QwtPlotMarker,
QwtSymbol,
)
from qwt.tests import utils
class DataPlot(QwtPlot):
def __init__(self, unattended=False):
QwtPlot.__init__(self)
self.setCanvasBackground(Qt.white)
self.alignScales()
# Initialize data
self.x = np.arange(0.0, 100.1, 0.5)
self.y = np.zeros(len(self.x), float)
self.z = np.zeros(len(self.x), float)
self.setTitle("A Moving QwtPlot Demonstration")
self.insertLegend(QwtLegend(), QwtPlot.BottomLegend)
self.curveR = QwtPlotCurve("Data Moving Right")
self.curveR.attach(self)
self.curveL = QwtPlotCurve("Data Moving Left")
self.curveL.attach(self)
self.curveL.setSymbol(
QwtSymbol(QwtSymbol.Ellipse, QBrush(), QPen(Qt.yellow), QSize(7, 7))
)
self.curveR.setPen(QPen(Qt.red))
self.curveL.setPen(QPen(Qt.blue))
mY = QwtPlotMarker()
mY.setLabelAlignment(Qt.AlignRight | Qt.AlignTop)
mY.setLineStyle(QwtPlotMarker.HLine)
mY.setYValue(0.0)
mY.attach(self)
self.setAxisTitle(QwtPlot.xBottom, "Time (seconds)")
self.setAxisTitle(QwtPlot.yLeft, "Values")
self.startTimer(10 if unattended else 50)
self.phase = 0.0
def alignScales(self):
self.canvas().setFrameStyle(QFrame.Box | QFrame.Plain)
self.canvas().setLineWidth(1)
for axis_id in QwtPlot.AXES:
scaleWidget = self.axisWidget(axis_id)
if scaleWidget:
scaleWidget.setMargin(0)
scaleDraw = self.axisScaleDraw(axis_id)
if scaleDraw:
scaleDraw.enableComponent(QwtAbstractScaleDraw.Backbone, False)
def timerEvent(self, e):
if self.phase > np.pi - 0.0001:
self.phase = 0.0
# y moves from left to right:
# shift y array right and assign new value y[0]
self.y = np.concatenate((self.y[:1], self.y[:-1]))
self.y[0] = np.sin(self.phase) * (-1.0 + 2.0 * random.random())
# z moves from right to left:
# Shift z array left and assign new value to z[n-1].
self.z = np.concatenate((self.z[1:], self.z[:1]))
self.z[-1] = 0.8 - (2.0 * self.phase / np.pi) + 0.4 * random.random()
self.curveR.setData(self.x, self.y)
self.curveL.setData(self.x, self.z)
self.replot()
self.phase += np.pi * 0.02
def test_data():
"""Data Test"""
utils.test_widget(DataPlot, size=(500, 300))
if __name__ == "__main__":
test_data()
