Question

我试图在Qt5应用程序中使用matplotlib来做一些实时图。根据Basti在博客上写的内容（http://bastibe.de/2013-05-30-speeding-up-matplotlib.html），专注于加快绘制图形。该示例基于matplotlib示例：embedding_in_qt5.py 我是ggplot的忠实粉丝，问题是当我更新图表时网格消失了。如果使用ggplot则无关紧要。这就是存在代码问题的地方：

#### FAST UPDATE VERSION - MISSING GRID ####

# Basti version
# self.axes.draw_artist(self.axes.patch)
# self.axes.draw_artist(lines[0])

# My version
# redraw_in_frame seems to do the same, but not much on the documentation
# https://matplotlib.org/api/_as_gen/matplotlib.axes.Axes.redraw_in_frame.html
self.axes.redraw_in_frame()
self.figure.canvas.update()
self.figure.canvas.flush_events()

#### SLOW VERSION - EVERYTHING (else) LOOKS GOOD ####
# self.draw()

问题的整个代码是

# embedding_in_qt5.py --- Simple Qt5 application embedding matplotlib canvases
#
# Copyright (C) 2005 Florent Rougon
#               2006 Darren Dale
#               2015 Jens H Nielsen
#
# This file is an example program for matplotlib. It may be used and
# modified with no restriction; raw copies as well as modified versions
# may be distributed without limitation.

import sys
import os
import matplotlib as plt
import matplotlib.pyplot as plty
import numpy as np
import time
plty.style.use('ggplot')
# Make sure that we are using QT5
plt.use('Qt5Agg')
from PyQt5 import QtCore, QtWidgets

# from numpy import arange, sin, pi
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.figure import Figure

progname = os.path.basename(sys.argv[0])
progversion = "0.1"


class MyMplCanvas(FigureCanvas):
    """Ultimately, this is a QWidget (as well as a FigureCanvasAgg, etc.)."""

    def __init__(self, parent=None, width=5, height=4, dpi=100):
        self.fig = Figure(figsize=(width, height), dpi=dpi)
        self.axes = self.fig.add_subplot(111)

        self.step = 0.05
        self.xaxis = np.arange(0, np.pi*2, self.step)
        self.yaxis = self.xaxis

        self.compute_initial_figure()

        # Time skip variable
        self.time_skip = 0
        FigureCanvas.__init__(self, self.fig)
        self.setParent(parent)

        FigureCanvas.setSizePolicy(self,
                                   QtWidgets.QSizePolicy.Expanding,
                                   QtWidgets.QSizePolicy.Expanding)
        FigureCanvas.updateGeometry(self)

    def compute_initial_figure(self):
        pass


class MyStaticMplCanvas(MyMplCanvas):
    """Simple canvas with a sine plot."""

    def compute_initial_figure(self):
        self.yaxis = np.sin(self.xaxis)
        self.axes.plot(self.xaxis, self.yaxis)
        self.axes.grid(True)


class MyDynamicMplCanvas(MyMplCanvas):
    """A canvas that updates itself every second with a new plot."""

    def __init__(self, *args, **kwargs):
        MyMplCanvas.__init__(self, *args, **kwargs)
        timer = QtCore.QTimer(self)
        timer.timeout.connect(self.update_figure)
        timer.start(25)

    def compute_initial_figure(self):
        self.axes.plot(self.xaxis, np.sin(self.yaxis))
        self.axes.grid(True)

    def update_figure(self):
        # skip a few timer events
        self.time_skip += 1
        if self.time_skip > 10:
            # Update the axis parameters to generate the sine
            self.yaxis += self.step
            # get the line
            lines = self.axes.get_lines()
            # and update it
            lines[0].set_ydata(np.sin(self.yaxis))

            #### FAST UPDATE VERSION - MISSING GRID ####
            # Basti version
            # self.axes.draw_artist(self.axes.patch)
            # self.axes.draw_artist(lines[0])

            # redraw_in_frame seems to do the same, but not much on the documentation
            # https://matplotlib.org/api/_as_gen/matplotlib.axes.Axes.redraw_in_frame.html
            self.axes.redraw_in_frame()
            self.figure.canvas.update()
            self.figure.canvas.flush_events()

            #### SLOW VERSION - EVERYTHING (else) LOOKS GOOD ####
            # self.draw()


class ApplicationWindow(QtWidgets.QMainWindow):
    def __init__(self):
        QtWidgets.QMainWindow.__init__(self)
        self.setAttribute(QtCore.Qt.WA_DeleteOnClose)
        self.setWindowTitle("application main window")

        self.file_menu = QtWidgets.QMenu('&File', self)
        self.file_menu.addAction('&Quit', self.fileQuit,
                                 QtCore.Qt.CTRL + QtCore.Qt.Key_Q)
        self.menuBar().addMenu(self.file_menu)

        self.help_menu = QtWidgets.QMenu('&Help', self)
        self.menuBar().addSeparator()
        self.menuBar().addMenu(self.help_menu)

        self.help_menu.addAction('&About', self.about)

        self.main_widget = QtWidgets.QWidget(self)

        l = QtWidgets.QVBoxLayout(self.main_widget)
        sc = MyStaticMplCanvas(self.main_widget, width=5, height=4, dpi=100)
        dc = MyDynamicMplCanvas(self.main_widget, width=5, height=4, dpi=100)
        l.addWidget(sc)
        l.addWidget(dc)

        self.main_widget.setFocus()
        self.setCentralWidget(self.main_widget)

        self.statusBar().showMessage("All hail matplotlib!", 2000)

    def fileQuit(self):
        self.close()

    def closeEvent(self, ce):
        self.fileQuit()

    def about(self):
        QtWidgets.QMessageBox.about(self, "About",
                                    """embedding_in_qt5.py example
Copyright 2005 Florent Rougon, 2006 Darren Dale, 2015 Jens H Nielsen

This program is a simple example of a Qt5 application embedding matplotlib
canvases.

It may be used and modified with no restriction; raw copies as well as
modified versions may be distributed without limitation.

This is modified from the embedding in qt4 example to show the difference
between qt4 and qt5"""
                                )


qApp = QtWidgets.QApplication(sys.argv)

aw = ApplicationWindow()
aw.setWindowTitle("%s" % progname)
aw.show()
sys.exit(qApp.exec_())
#qApp.exec_()

使用pyqtgraph对我来说不是一个简单的解决方案，因为我对它的样式不是很有信心 - 所以除非有use('ggplot')我正在寻求这个解决方案。

matplotlib重绘删除背景

0 个答案: