Ralph,
Perhaps time to migrate to Chaco API from Enthought? not sure if there is Ubuntu support yet however. Alex Baker http://code.enthought.com/chaco/ Ralf Gommers-2 wrote: > > Hi, > > I am working on a PyQt4 application with some embedded MPL figures, and am > also trying to save some figures as png's without displaying them. I am > observing huge memory increases (10s or 100s of Mb) the moment I try to > save > a png. I reproduced the issue by combining two mpl examples, > http://matplotlib.sourceforge.net/examples/user_interfaces/embedding_in_qt4.htmland > http://matplotlib.sourceforge.net/examples/api/agg_oo.html. Full code is > attached. When pressing the "save figure" button, memory usage shoots up, > multiple clicks keep sending it higher (although not monotonically). > > I tested on two different platforms > - Matplotlib 98.5.2 and Python 2.6.2 on Ubuntu. > - latest Enthought Python Distribution on Windows XP. > > The function that does the png saving is: > > def save_png(): > """Save an image as a png file""" > > pngpath = 'test_mplsave.png' > > fig = Figure() > canvas = FigureCanvas(fig) > ax = fig.add_subplot(111) > x = arange(5e3) > ax.plot(x, sin(x)) > canvas.print_figure(pngpath) > > ## tried all things commented out below, all makes no difference ## > #fig.savefig(pngpath) > > #del(fig) > #del(canvas) > #del(ax) > > #import matplotlib.pyplot as plt > #plt.close(fig) > > #import gc > #gc.collect() > > Commenting out the canvas.print_figure line fixes the issue. > > Am I doing something obviously wrong, or mixing two incompatible ways of > doing things? > > Cheers, > Ralf > > #!/usr/bin/env python > > # embedding_in_qt4.py --- Simple Qt4 application embedding matplotlib > canvases > # > # Copyright (C) 2005 Florent Rougon > # 2006 Darren Dale > # > # 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, os, random > from PyQt4 import QtGui, QtCore > > from numpy import arange, sin, pi > from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as > FigureCanvas > from matplotlib.figure import Figure > > > 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): > fig = Figure(figsize=(width, height), dpi=dpi) > self.axes = fig.add_subplot(111) > # We want the axes cleared every time plot() is called > self.axes.hold(False) > > self.compute_initial_figure() > > FigureCanvas.__init__(self, fig) > self.setParent(parent) > > FigureCanvas.setSizePolicy(self, > QtGui.QSizePolicy.Expanding, > QtGui.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): > t = arange(0.0, 3.0, 0.01) > s = sin(2*pi*t) > self.axes.plot(t, s) > > > def save_png(): > """Save an image as a png file""" > > pngpath = 'test_mplsave.png' > > fig = Figure() > canvas = FigureCanvas(fig) > ax = fig.add_subplot(111) > x = arange(5e3) > ax.plot(x, sin(x)) > #canvas.print_figure(pngpath) > > ## tried all things commented out below, all makes no difference ## > #fig.savefig(pngpath) > > #del(fig) > #del(canvas) > #del(ax) > > #import matplotlib.pyplot as plt > #plt.close(fig) > > #import gc > #gc.collect() > > > class ApplicationWindow(QtGui.QMainWindow): > def __init__(self): > QtGui.QMainWindow.__init__(self) > self.setAttribute(QtCore.Qt.WA_DeleteOnClose) > self.setWindowTitle("application main window") > > self.file_menu = QtGui.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 = QtGui.QMenu('&Help', self) > > self.main_widget = QtGui.QWidget(self) > > l = QtGui.QVBoxLayout(self.main_widget) > sc = MyStaticMplCanvas(self.main_widget, width=5, height=4, > dpi=100) > dc = QtGui.QPushButton('Save image') > l.addWidget(sc) > l.addWidget(dc) > > self.main_widget.setFocus() > self.setCentralWidget(self.main_widget) > > self.statusBar().showMessage("All hail matplotlib!", 2000) > self.connect(dc, QtCore.SIGNAL("clicked()"), save_png) > > def fileQuit(self): > self.close() > > def closeEvent(self, ce): > self.fileQuit() > > > qApp = QtGui.QApplication(sys.argv) > > aw = ApplicationWindow() > aw.setWindowTitle("Try saving a simple png image") > aw.show() > sys.exit(qApp.exec_()) > > ------------------------------------------------------------------------------ > > _______________________________________________ > Matplotlib-users mailing list > Matplotlib-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/matplotlib-users > > -- View this message in context: http://www.nabble.com/memory-leak-with-PyQt4-plus-savefig-or-print_figure-tp24298299p24603899.html Sent from the matplotlib - users mailing list archive at Nabble.com. ------------------------------------------------------------------------------ _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
