[Matplotlib-users] memory problem

[Humufr <hu...@ya...>]

                    Hi,

on a pc with linux and 512M of RAM, I have a problem of memory when I'm 
using matplotlib.

from pylab import *
imshow(zeros((2000,2000)))
show()

is working but:

from pylab import *
imshow(zeros((4000,4000)))
show()

is not.


That slow down the computer, it close to be freeze and I obtain this 
error (the two error message for show() and savefig('test.png') are at 
the bottom of the mail. (matshow give exactly the same result)

It's a big problem, for me at least, because I'm working with some image 
with 4000x4000 pixels.

Thanks,

       N.

Exception in Tkinter callback
Traceback (most recent call last):
  File "/usr/local/lib/python2.4/lib-tk/Tkinter.py", line 1345, in __call__
    return self.func(*args)
  File 
"/usr/local/lib/python2.4/site-packages/matplotlib/backends/backend_tkagg.py", 
line 140, in resize
    self.show()
  File 
"/usr/local/lib/python2.4/site-packages/matplotlib/backends/backend_tkagg.py", 
line 143, in draw
    FigureCanvasAgg.draw(self)
  File 
"/usr/local/lib/python2.4/site-packages/matplotlib/backends/backend_agg.py", 
line 312, in draw
    self.figure.draw(renderer)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/figure.py", 
line 395, in draw
    for a in self.axes: a.draw(renderer)
  File 
"/scratch/gruel/usr/local/lib/python2.4/site-packages/matplotlib/axes.py", 
line 1339, in draw
    im.draw(renderer)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/image.py", 
line 182, in draw
    im = self.make_image(isUpper)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/image.py", 
line 112, in make_image
    x = self.to_rgba(self._A, self._alpha)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/cm.py", line 
418, in to_rgba
    return self.cmap(x, alpha)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/colors.py", 
line 526, in __call__
    rgba = zeros(xa.shape+(4,), Float)
  File 
"/usr/local/lib/python2.4/site-packages/numarray/numarraycore.py", line 
1407, in zeros
    retarr = NumArray(shape=shape, type=type)
MemoryError: Couldn't allocate requested memory


I did the same with savefig

Traceback (most recent call last):
  File "test.py", line 12, in ?
    savefig('test.png')
  File 
"/scratch/gruel/usr/local/lib/python2.4/site-packages/matplotlib/pylab.py", 
line 719, in savefig
    return fig.savefig(*args, **kwargs)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/figure.py", 
line 512, in savefig
    self.canvas.print_figure(*args, **kwargs)
  File 
"/usr/local/lib/python2.4/site-packages/matplotlib/backends/backend_tkagg.py", 
line 161, in print_figure
    agg.print_figure(filename, dpi, facecolor, edgecolor, orientation)
  File 
"/usr/local/lib/python2.4/site-packages/matplotlib/backends/backend_agg.py", 
line 375, in print_figure
    self.draw()
  File 
"/usr/local/lib/python2.4/site-packages/matplotlib/backends/backend_agg.py", 
line 312, in draw
    self.figure.draw(renderer)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/figure.py", 
line 395, in draw
    for a in self.axes: a.draw(renderer)
  File 
"/scratch/gruel/usr/local/lib/python2.4/site-packages/matplotlib/axes.py", 
line 1339, in draw
    im.draw(renderer)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/image.py", 
line 182, in draw
    im = self.make_image(isUpper)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/image.py", 
line 112, in make_image
    x = self.to_rgba(self._A, self._alpha)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/cm.py", line 
418, in to_rgba
    return self.cmap(x, alpha)
  File "/usr/local/lib/python2.4/site-packages/matplotlib/colors.py", 
line 526, in __call__
    rgba = zeros(xa.shape+(4,), Float)
  File 
"/usr/local/lib/python2.4/site-packages/numarray/numarraycore.py", line 
1407, in zeros
    retarr = NumArray(shape=shape, type=type)
MemoryError: Couldn't allocate requested memory