[Matplotlib-users] Segmentation fault in Pyqt

[Sourabh B. <sb...@gm...>]

I am getting a segmentation fault when I try to declare a new image name. I
can replace a existing image correctly. Why am I getting the error at the
getSaveFileName dialog ??

Can anyone help me with the code.


import sys

from PyQt4 import QtGui, QtCore, Qt

import numpy as np

from matplotlib.figure import Figure

import matplotlib.pyplot as plt

from mpl_toolkits.mplot3d import Axes3D

from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as
FigureCanvas

from matplotlib.backends.backend_qt4agg import NavigationToolbar2QTAgg as
NavigationToolbar


def randrange(n, vmin, vmax):

    return (vmax-vmin)*np.random.rand(n) + vmin


class Example(QtGui.QWidget):



def __init__(self):

super(Example, self).__init__()

self.initUI()



def initUI(self):

self.main_frame = QtGui.QWidget()

self.dpi=100

self.i=1

self.fig = Figure((5.0, 5.0), dpi=self.dpi)

self.scatterpts = []

self.canvas = FigureCanvas(self.fig)

self.canvas.setParent(self.main_frame)

self.ax = self.fig.gca(projection='3d')

self.mpl_toolbar = NavigationToolbar(self.canvas, self.main_frame)

self.btn = QtGui.QPushButton('Button', self)

self.btn.resize(self.btn.sizeHint())

self.btn.clicked.connect(self.drawplot)


self.btn1 = QtGui.QPushButton('Save', self)

self.btn1.resize(self.btn.sizeHint())

self.btn1.clicked.connect(self.saveplot)



self.setWindowTitle('Tooltips')

 Box =QtGui.QVBoxLayout()

Box.addWidget(self.canvas)

Box.addWidget(self.btn)

Box.addWidget(self.btn1)

Box.addWidget(self.mpl_toolbar)

self.main_frame.setLayout(Box)

self.main_frame.show()


def drawplot(self):


if self.i==0:

for pt in self.scatterpts :

pt.remove()

self.scatterpts = []


n = 500

for c, m, zl, zh in [('r', 'o', -50, -25), ('b', '^', -30, -5)]:

xs = randrange(n, 23, 32)

ys = randrange(n, 0, 100)

zs = randrange(n, zl, zh)

pt = self.ax.scatter(xs, ys, zs, c=c, marker=m, s=40)

self.scatterpts.append(pt)


self.ax.set_xlabel('X Label')

self.ax.set_ylabel('Y Label')

self.ax.set_zlabel('Z Label')

self.canvas.draw()

self.canvas.print_figure('trial.png', dpi=self.dpi)

self.i=0


def saveplot(self):

fname = QtGui.QFileDialog.getSaveFileName(self, 'Save file',
'/home/untitled.png', 'Images (*.png *.xpm *.jpg)')

self.canvas.print_figure(fname, dpi=100)


def main():



    app = QtGui.QApplication(sys.argv)

    ex = Example()

    sys.exit(app.exec_())



if __name__ == '__main__':

    main()