matplotlib-users Mailing List for matplotlib (Page 2)

Hi,
I'm in the way of rewriting in Python from scratch an old matlab data
analysis program for AFM data. The program should have a quite simple
GUI with a graph capable of interactive plotting (i.e. clicking on two
points on a 2d graph and fitting the points in between) and a couple of
buttons/menus for fit options and graph options. It's a couple of days
I'm learning matplotlib/pylab and scipy, and they seem powerful enough
to fulfill my needs.

Now, my dream would be to embed matplotlib in a full WxPython
application, instead of using pylab, but (1)I have read that it requires
to rewrite some basic pylab facilities, like taking plot coordinates of
the mouse, that I really need and that's very easy to use (2)I still
have to learn WxPython, and even if I'd eventually do it, it seems messy 
to me to learn WxPython and to embed matplotlib in it at the same time 
(3)I have not so much time...I have to analyze that data, more sooner 
than later. :( I think I'll eventually do an embedded matplotlib 
application, but I'd like to think about it as "version 2.0".

So, there are two solutions that I'm considering:
- Using WxMpl or MPlot. What are pros and cons of both wrappers?
- Creating a small, pure WxPython application that calls pylab to manage 
graph operations. I think it would look somehow like Gimp, with a tall 
and thin window full of buttons, menus etc. and the graph as a separate 
pylab window.

What's the best alternative and/or your advice and critics about it?

Thanks,
Massimo

-- 
Massimo Sandal
University of Bologna
Department of Biochemistry "G.Moruzzi"

snail mail:
Via Irnerio 48, 40126 Bologna, Italy

email:
mas...@un...

tel: +39-051-2094388
fax: +39-051-2094387

On Tue, 2005-11-29 at 12:25 +0100, Willi Richert wrote:
> I need to draw a sequence of arrows denoting a path. There is the quiver 
> function which draws vector fields (and, btw, behaves differently from the 
> examples on the web), so this is not an option. Additionally, there is the 
> Arrow class. But it is very slow and, what's more important, draws distortet 
> arrows at some angles. Am I missing something, or are these two possibilities 
> the only options?

As far as I know these are the only two options at the moment.  If you
are happy patching the matplotlib source then you could use this patch I
wrote a while ago which implements an arrowhead line marker (specify
'-a' as the style in a plot command or use the keyword argument
marker="a", linestyle="-").  This patch is limited in that if you make
the linewidth greater than around 1 the end of the line will be visible
after the last arrow.  Unfortunately to fix this would require doing
something more than just implementing a new marker style.

Nicholas Young

Hi Eric,

On Tue, 29 Nov 2005, Eric Emsellem wrote:

> Hi,
> I have installed python2.4, the last versions of scipy and numarray, and
> matplotlib 0.85.
> I have now constant problems trying to use my scripts, where I often
> make use of arrays.
> It often gives me things like:
>
> ==========
> /usr/lib/python2.4/site-packages/numarray/numarraycore.py:376:
> UserWarning: __array__ returned non-NumArray instance
>   _warnings.warn("__array__ returned non-NumArray instance")
> ---------------------------------------------------------------------------
> numarray.libnumarray.error                                     Traceback
> (most recent call last)
> ...
> error: Type object lookup returned NULL for type -1
> ==========
>
> or similar problems which seems linked to the fact that somehow my
> arrays have :
>
> <type 'scipy.ndarray'>
>
> So if I try to do for example:
>    plot(x,y)
>
> where x and y seem to be scipy.ndarray, it crashes with errors such as
> the one mentioned above.
> (I tried to cast them as numarray.asarray but it keeps its scipy.ndarray
> whatever I do...)

Do you have simple example which reproducibly gives the above error?
(Just to be sure: are you using the new scipy, or the old one?)

Best, Arnd

Hi,
I have installed python2.4, the last versions of scipy and numarray, and 
matplotlib 0.85.
I have now constant problems trying to use my scripts, where I often 
make use of arrays.
It often gives me things like:

==========
/usr/lib/python2.4/site-packages/numarray/numarraycore.py:376: 
UserWarning: __array__ returned non-NumArray instance
  _warnings.warn("__array__ returned non-NumArray instance")
---------------------------------------------------------------------------
numarray.libnumarray.error                                     Traceback 
(most recent call last)
...
error: Type object lookup returned NULL for type -1
==========

or similar problems which seems linked to the fact that somehow my 
arrays have :

<type 'scipy.ndarray'>

So if I try to do for example:
   plot(x,y)

where x and y seem to be scipy.ndarray, it crashes with errors such as 
the one mentioned above.
(I tried to cast them as numarray.asarray but it keeps its scipy.ndarray 
whatever I do...)

So my question is :

- does anybody know what really changed in the last versions of 
scipy/numarray/matplotlib which now induces these crashes (before all 
was fine) ?

- what should I do to solve it (maybe I have to systematically use 
numarray functions by specifying "numarray." in front of all the 
"zeros", "arange" and so on..., but I have the impression this may not 
solve everything) ?

- how do I transform a scipy.ndarray into something compatible for 
matplotlib?

thanks for the help (I realize this is maybe more a numarray/scipy 
question, but maybe someone from the matplotlib crowd can help me: it 
seems that most of my scripts are crashing in similar ways - probably 
bad writing on my side... but I am here to learn..)

Eric

== for info, I use:
matplotlib version 0.85
platform is linux2
numerix numarray 1.4.1
backend GTKAgg version 2.8.0
Python 2.4.1 (#1, Sep 13 2005, 00:39:20)
IPython 0.6.15 -- An enhanced Interactive Python.

-- 
===============================================================
Observatoire de Lyon                 ems...@ob...
9 av. Charles-Andre                      tel: +33 4 78 86 83 84
69561 Saint-Genis Laval Cedex            fax: +33 4 78 86 83 86
France               http://www-obs.univ-lyon1.fr/eric.emsellem
===============================================================

Hi,

I need to draw a sequence of arrows denoting a path. There is the quiver 
function which draws vector fields (and, btw, behaves differently from the 
examples on the web), so this is not an option. Additionally, there is the 
Arrow class. But it is very slow and, what's more important, draws distortet 
arrows at some angles. Am I missing something, or are these two possibilities 
the only options?



Thanks,
wr

John,

I think that the changes I made in CVS over the weekend provide a much 
easier way to do this, as illustrated in the new examples/image_masked.py.

Eric

John Hunter wrote:
>>>>>>"Danny" == Danny Shevitz <sh...@la...> writes:
> 
> 
>     Danny> I just got back from vacation sorry for the delay.  If you
>     Danny> haven't worked out your own solution yet, I took John's
>     Danny> suggestions and made some very minor additions to them. If
>     Danny> you are interested, I can post the resulting code which
>     Danny> allows you to specify a base colormap and then override
>     Danny> arbitrary sentinels with specified colors.
> 
>     Danny> One problem with John's algorithm as written in his
>     Danny> original post, was that the sentinel was included in the
>     Danny> normalization and should not be.
> 
> I think this would make a nice wiki entry if you get the time.
> 
> http://www.scipy.org/wikis/topical_software/MatplotlibCookbook
> 
> 
> 
> JDH
> 
> 
> -------------------------------------------------------
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>>>>> "Danny" == Danny Shevitz <sh...@la...> writes:

    Danny> I just got back from vacation sorry for the delay.  If you
    Danny> haven't worked out your own solution yet, I took John's
    Danny> suggestions and made some very minor additions to them. If
    Danny> you are interested, I can post the resulting code which
    Danny> allows you to specify a base colormap and then override
    Danny> arbitrary sentinels with specified colors.

    Danny> One problem with John's algorithm as written in his
    Danny> original post, was that the sentinel was included in the
    Danny> normalization and should not be.

I think this would make a nice wiki entry if you get the time.

http://www.scipy.org/wikis/topical_software/MatplotlibCookbook



JDH

I just got back from vacation sorry for the delay.

If you haven't worked out your own solution yet, I took John's suggestions 
and made some very minor additions to them. If you are interested, I can 
post the resulting code which allows you to specify a base colormap and 
then override arbitrary sentinels with specified colors.

One problem with John's algorithm as written in his original post, was that 
the sentinel was included in the normalization and should not be.

D


At 09:21 PM 11/25/2005 -0600, you wrote:
> >>>>> "Gerald" == Gerald John M Manipon 
> <Ger...@jp...> writes:
>
>     Gerald> Hello, I'm trying to plot some grid data using basemap and
>     Gerald> imshow however haven't figured out how to specify the
>     Gerald> color for nan values.  For example, in my data, valid
>     Gerald> values range from 0.0-10.0.  I've assigned -9999.0 and
>     Gerald> 1e30 to the missing values and when I imshow (setting
>     Gerald> vmin=0.0, vmax=10.0), the missing values show up in the
>     Gerald> low and high end of the spectrum, respectively.  Is there
>     Gerald> a way to do this?
>
>See the archives for a post by Danny Shevitz and followups in the
>thread "obscure colormapping issue related to quantization"
>
>http://article.gmane.org/gmane.comp.python.matplotlib.general/2856/match=obscure+colormapping+issue+related+to+quantization
>
>Basically, you want to write a custom normalization and colormapping
>instance, and recipe code is posted in the thread linked above.
>
>JDH
>
>
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These are some very basic installation questions from someone
upgrading from 10.3 to 10.4 OS X.  I installed the 2.4.1 binary
installation of python on 10.4.3 OS X.  I also installed (the amazing)
ipython and Tcl/Tk Aqua which seem to work.  Instead of using a v0.82
binary package of matplotlib I decided to try building from the 0.85
release.

This has been more of a challenge than I expected.  I
compiled/installed versions of freetype and libpng but I'm not really
sure if or how to get matplotlib to find them.  Anyway, I didn't
notice errors when matplotlib installed but when running ipython and
typing import pylab I get the exception below.  Does anyone have a
suggestion for what might be wrong?


/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packag=
es/matplotlib/font_manager.py
     37 import matplotlib
     38 from matplotlib import afm
---> 39 from matplotlib import ft2font
     40 from matplotlib import rcParams, get_data_path, get_home, get_confi=
gdir
     41

ImportError: Failure linking new module:
/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packag=
es/matplotlib/ft2font.so:
Symbol not found: _vsprintf$LDBLStub
  Referenced from:
/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packag=
es/matplotlib/ft2font.so
  Expected in: dynamic lookup



Also I noticed that darwinports has freetype, etc, and seems much
easier to use to install and manage various unix tools and libraries.
It seems to like to put everything in /opt/local/.  How can I get
matplotlib to check there for libraries (assuming that's the problem)?

-- David

On Nov 26, 2005, at 11:13 PM, Tim Burgess wrote:
> Can anyone post some code that will print a wxmpl figure?

WxMpl already includes printing support, in the form of  
wxmpl.FigurePrinter.  Have you tried it yet, and if so, does it also  
have the zero-byte print job problem?

Ken

Tim,

Does the example code at    http://cars9.uchicago.edu/~newville/Python/MPlo=
t/
help at all?  I admit I haven't tried this on a linux box in a while,
and maybe not with very recent matplotlib versions.   But it works for
me on Windows and Mac, and has worked on linux boxes too.  The code
there should definitely be a reasonable place to start.

Cheers,

--Matt Newville <newville at cars.uchicago.edu>

On 11/26/05, Tim Burgess <ti...@tb...> wrote:
> Hi all,
> I am struggling with printing from wxpython. Please dont refer me to the
> wxpython wiki - been there done that.
>
> I have two almost identical snippets of code to perform a print preview
> and a paper print of a wxmpl figure. The print preview works
> brilliantly, print to paper - nothing happens on the paper. A 0 byte
> print job flashes through the windows print spooler and that's it.
>
> For text reports I got easy html printing going - that was indeed
> easy.... but I fought and fought with wxPrintout and gave up.... I had
> exactly the same problem - print preview worked fine - but print paper -
> empty print jobs.. I am missing something - but I dont know what. Please
> not the wiki - it's not helping me - it normally is fantastic.
>
> Can anyone post some code that will print a wxmpl figure? Here's mine -
> it's in a state after several days of failed attempts....
>
>                 self.printer_config =3D wx.PrintData()
>                 print "Printer is: ",
> self.printer_config.GetPrinterName()  # no printer name is reported here =
-
>
>                             # yet a print job is sent to the pritner
>
> self.printer_config.SetPaperId(wx.PAPER_A4_ROTATED)
>                 tim =3D wxmpl.FigurePrinter(self,self.printer_config)
>                 tim.printFigure(self.ProdGraph.get_figure(), "Production
> Schedule")
>
> Plan B - my customer wants the graph on paper - he doesnt care how I do
> it - and right now neither do I
> I have wxmpl making a png image in a file - can some one give me the
> minimum lines of code - to get the png on paper - please. Lets say the
> file is called graph.png.
>
> Thanks
>
> --
> Tim Burgess
> IT Consultant
> RedHat Certified Engineer
> TBITC Pty Ltd
> Professional Computer Support for Business
> ti...@tb...
> Mobile 0422 942 972
> Office 85 662 016
> http://www.tbitc.com
>
>
>
> -------------------------------------------------------
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les
> for problems?  Stop!  Download the new AJAX search engine that makes
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>

On Sun, 27 Nov 2005, Tim Burgess apparently wrote: 
> I am struggling with printing from wxpython. Please dont refer me to the 
> wxpython wiki - been there done that. 

> Plan B - my customer wants the graph on paper - he doesnt care how I do 
> it - and right now neither do I 
> I have wxmpl making a png image in a file - can some one give me the 
> minimum lines of code - to get the png on paper - please. Lets say the 
> file is called graph.png. 

http://tgolden.sc.sabren.com/python/win32_how_do_i/print.html

hth,
Alan Isaac

Hi all,
I am struggling with printing from wxpython. Please dont refer me to the 
wxpython wiki - been there done that.

I have two almost identical snippets of code to perform a print preview 
and a paper print of a wxmpl figure. The print preview works 
brilliantly, print to paper - nothing happens on the paper. A 0 byte 
print job flashes through the windows print spooler and that's it.

For text reports I got easy html printing going - that was indeed 
easy.... but I fought and fought with wxPrintout and gave up.... I had 
exactly the same problem - print preview worked fine - but print paper - 
empty print jobs.. I am missing something - but I dont know what. Please 
not the wiki - it's not helping me - it normally is fantastic.

Can anyone post some code that will print a wxmpl figure? Here's mine - 
it's in a state after several days of failed attempts....
               
                self.printer_config = wx.PrintData()
                print "Printer is: ", 
self.printer_config.GetPrinterName()  # no printer name is reported here -
                                                                        
                            # yet a print job is sent to the pritner
                
self.printer_config.SetPaperId(wx.PAPER_A4_ROTATED)                
                tim = wxmpl.FigurePrinter(self,self.printer_config)
                tim.printFigure(self.ProdGraph.get_figure(), "Production 
Schedule") 

Plan B - my customer wants the graph on paper - he doesnt care how I do 
it - and right now neither do I
I have wxmpl making a png image in a file - can some one give me the 
minimum lines of code - to get the png on paper - please. Lets say the 
file is called graph.png.

Thanks

-- 
Tim Burgess
IT Consultant
RedHat Certified Engineer
TBITC Pty Ltd
Professional Computer Support for Business
ti...@tb...
Mobile 0422 942 972
Office 85 662 016
http://www.tbitc.com

Hi,

I'm relatively new to python and matplotlib and trying to make a graph with
an inset.

How do I control the size of the text in the legend, made using figlegend?

I've tried to do something like this:

leg =3D figlegend(lines,(r'$r_f =3D 1.5d$',r'$r_f =3D 2d$',r'$r_f =3D 4d$',
                       r'$r_f =3D 6d$'),(0.7,0.7))
legLbls =3D leg.get_texts()
set(legLbls,fontsize=3D24)

but that seems to have no effect.

Also, how do I change the frequency of the tick labeling?  I want to label
over other tick instead of every tick in the inset figure.  Right now it is
too busy.

So far, matplotlib looks great!  Thanks for all the hard work.

Thanks,
James

--
James W. Landry
jwl...@gm...

It works fine in TkAgg.  That implies that you are right and it is a
threading problem in pygtk.  Thanks a lot for tracking this down.

James Landry

On 11/25/05, John Hunter <jdh...@ac...> wrote:
>
> >>>>> "James" =3D=3D James Landry <jwl...@gm...> writes:
>
>     James> Maybe this is a dumb question, but I've installed tk-devel
>     James> and tcl-devel.  Still doesn't work.  Do I need to reinstall
>     James> matplotlib or do it from source?
>
> Yes, after installing the dev headers you will need to rebuild
> matplotlib from src.  I suggest you capture the output of the build
> process is case you need to post it
>
> > sudo rm -rf build
> > sudo python setup.py install >& build.out
>
> JDH
>
>     James> James
>
>     James> On 11/25/05, John Hunter <jdh...@ac...>
>     James> wrote:
>     >>  >>>>> "James" =3D=3D James Landry <jwl...@gm...> writes:
>     >>
>     James> I get the following message, when I try to use it, which I
>     James> don't understand, because I have tkinter installed:
>     >>  It means that matpltolib was not able to find the tk src code
>     >> needed to compile the tkagg extension.  Usually this is because
>     >> you haven't installed the tk-dev and tcl-dev packages.
>     >>
>     >> JDH
>     >>
>
>
>
>     James> -- James W. Landry jwl...@gm...
>



--
James W. Landry
jwl...@gm...

>>>>> "James" == James Landry <jwl...@gm...> writes:

    James> Maybe this is a dumb question, but I've installed tk-devel
    James> and tcl-devel.  Still doesn't work.  Do I need to reinstall
    James> matplotlib or do it from source?

Yes, after installing the dev headers you will need to rebuild
matplotlib from src.  I suggest you capture the output of the build
process is case you need to post it

> sudo rm -rf build
> sudo python setup.py install >& build.out

JDH

    James> James

    James> On 11/25/05, John Hunter <jdh...@ac...>
    James> wrote:
    >>  >>>>> "James" == James Landry <jwl...@gm...> writes:
    >> 
    James> I get the following message, when I try to use it, which I
    James> don't understand, because I have tkinter installed:
    >>  It means that matpltolib was not able to find the tk src code
    >> needed to compile the tkagg extension.  Usually this is because
    >> you haven't installed the tk-dev and tcl-dev packages.
    >> 
    >> JDH
    >> 



    James> -- James W. Landry jwl...@gm...

Maybe this is a dumb question, but I've installed tk-devel and tcl-devel.
Still doesn't work.  Do I need to reinstall matplotlib or do it from source=
?

James

On 11/25/05, John Hunter <jdh...@ac...> wrote:
>
> >>>>> "James" =3D=3D James Landry <jwl...@gm...> writes:
>
>     James> I get the following message, when I try to use it, which I
>     James> don't understand, because I have tkinter installed:
>
> It means that matpltolib was not able to find the tk src code needed
> to compile the tkagg extension.  Usually this is because you haven't
> installed the tk-dev and tcl-dev packages.
>
> JDH
>



--
James W. Landry
jwl...@gm...

>>>>> "James" == James Landry <jwl...@gm...> writes:

    James> I get the following message, when I try to use it, which I
    James> don't understand, because I have tkinter installed:

It means that matpltolib was not able to find the tk src code needed
to compile the tkagg extension.  Usually this is because you haven't
installed the tk-dev and tcl-dev packages.

JDH

I tried using tkagg by setting

backend  : TkAgg

in my matplotlibrc, which includes only the following lines:

backend         : TkAgg

# latex options for matplotlib

font.latex.package    : type1cm
text.usetex        : False
text.tex.engine        : latex

I get the following message, when I try to use it, which I don't understand=
,
because I have tkinter installed:

[jwlandry@merrimac flow]$ ~/grain/plots/hopper/pof-w-insert.py data_hopper-
40k-r1.5.funnel-pof.combo data_hopper-40k-r2.funnel-pof.combo data_hopper-
40k-r4.funnel-pof.combo data_hopper-40k-r6.funnel-pof.combo
Traceback (most recent call last):
  File "/home/jwlandry/grain/plots/hopper/pof-w-insert.py", line 12, in ?
    from pylab import *
  File "/usr/lib/python2.4/site-packages/pylab.py", line 1, in ?
    from matplotlib.pylab import *
  File "/usr/lib/python2.4/site-packages/matplotlib/pylab.py", line 217, in
?
    new_figure_manager, draw_if_interactive, show =3D pylab_setup()
  File "/usr/lib/python2.4/site-packages/matplotlib/backends/__init__.py",
line 24, in pylab_setup
    globals(),locals(),[backend_name])
  File
"/usr/lib/python2.4/site-packages/matplotlib/backends/backend_tkagg.py",
line 8, in ?
    import tkagg                 # Paint image to Tk photo blitter extensio=
n
  File "/usr/lib/python2.4/site-packages/matplotlib/backends/tkagg.py", lin=
e
1, in ?
    import _tkagg
ImportError: No module named _tkagg

James

On 11/25/05, John Hunter <jdh...@ac...> wrote:
>
> >>>>> "James" =3D=3D James Landry <jwl...@gm...> writes:
>
>     James> When it doesn't work, a dialog box opens with this message
>
>     James> Save figure failure: None: Interrupted system call
>
> What backend are you using?  I have seen something like this on GTK*.
> I'm pretty sure it is a threading problem.  Basically, we need a
> backend dependent thread-safe way to make system calls.  Not a trivial
> task.  I've posted a thread about this to the pygtk mailing list a few
> months ago, but have yet to find a reliable recipe.  gtk gurus, please
> advise.
>
> In the meantime, you may want to try a different GUI backend, eg,
> tkagg.  If this helps, let us know, because it will help determine
> that this is indeed your problem.
>
>
> JDH
>



--
James W. Landry
jwl...@gm...

>>>>> "Charlie" =3D=3D Charlie Moad <cw...@gm...> writes:

    Charlie> Can anybody think of a good way to disable a widget
    Charlie> (specifically SpanSelector) during plot interaction from
    Charlie> the toolbar?  It seems wrong when you are panning and the
    Charlie> SpanSelector is triggering over and over.  Is there a
    Charlie> trivial way to detect the state of the toolbar?

I think this will require some minor tweaks to backend_bases
NavigationToolbar2 and SpanSelector.  You'll want to modify
NavigationToolbar2 to make the mode "publicly accessible", eg a
get_mode method, which returns None, 'pan/zoom', or 'zoom-to-rect'
using the underlying _idPress, _idRelease, et al.  Then you'll want to
modify the span selector to be toolbar aware, eg, something along the
lines of

toolbar =3D getattr(self.ax.figure.canvas, 'toolbar')
if toolbar is not None:
    mode =3D toolbar.get_mode()
    if mode is None: suppress drawing....

The getattr check is required in case someone is using the span
selector in a canvas w/o the toolbar.
JDH

    Charlie> Thanks, Charlie


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    Charlie> Matplotlib-users mailing list
    Charlie> Mat...@li...
    Charlie> https://lists.sourceforge.net/lists/listinfo/matplotlib-user=
s

>>>>> "Gerald" == Gerald John M Manipon <Ger...@jp...> writes:

    Gerald> Hello, I'm trying to plot some grid data using basemap and
    Gerald> imshow however haven't figured out how to specify the
    Gerald> color for nan values.  For example, in my data, valid
    Gerald> values range from 0.0-10.0.  I've assigned -9999.0 and
    Gerald> 1e30 to the missing values and when I imshow (setting
    Gerald> vmin=0.0, vmax=10.0), the missing values show up in the
    Gerald> low and high end of the spectrum, respectively.  Is there
    Gerald> a way to do this?

See the archives for a post by Danny Shevitz and followups in the
thread "obscure colormapping issue related to quantization"

http://article.gmane.org/gmane.comp.python.matplotlib.general/2856/match=obscure+colormapping+issue+related+to+quantization

Basically, you want to write a custom normalization and colormapping
instance, and recipe code is posted in the thread linked above.

JDH

>>>>> "Alan" == Alan Jackson <aja...@op...> writes:
    Alan> to show the failure, I thought I would ask to see of there
    Alan> are known incompatibilities between Linux and XP that might
    Alan> be causing my problem.

No, none that I am aware of.  I suggest you come up with that demo
script.


JDH

>>>>> "James" == James Landry <jwl...@gm...> writes:

    James> When it doesn't work, a dialog box opens with this message

    James> Save figure failure: None: Interrupted system call

What backend are you using?  I have seen something like this on GTK*.
I'm pretty sure it is a threading problem.  Basically, we need a
backend dependent thread-safe way to make system calls.  Not a trivial
task.  I've posted a thread about this to the pygtk mailing list a few
months ago, but have yet to find a reliable recipe.  gtk gurus, please
advise.

In the meantime, you may want to try a different GUI backend, eg,
tkagg.  If this helps, let us know, because it will help determine
that this is indeed your problem.


JDH

Thanks for the suggestion Jose.  I installed the new version and the same
problem appeared again.  I'm getting some ideas though.  When I tried it
again by uncommenting the rc line, it worked the first time but not the
second.  Doesn't it cache some of the information?  Could that be the
problem?

James Landry

On 11/25/05, Jos=E9 Matos <jao...@gm...> wrote:
>
> On 25/11/05, James Landry <jwl...@gm...> wrote:
> > I have intermittent problems with the savefig('foo.eps') command when I
> am
> > using my native LaTeX interpreter to produce eps files.  The really
> > frustrating thing is that it is intermittent.  Sometimes I can save a
> file
> > that looks fine and sometimes I can't.
> >
> >  My box is running Fedora Core 4 and kernel 2.6.14.
> >
> >  I have the following rpms:
> >  python-2.4.1-2
> >  ipython-0.6.15-1.fc4
> >  python-tools-2.4.1-2
> >  python-matplotlib-0.84-1.fc4
> >  python-numeric-23.7-2
>
>   Probably it is irrelevant to this problem and it does not help here
> but notice that 0.85 is available from extras.
>



--
James W. Landry
jwl...@gm...

I have intermittent problems with the savefig('foo.eps') command when I am
using my native LaTeX interpreter to produce eps files.  The really
frustrating thing is that it is intermittent.  Sometimes I can save a file
that looks fine and sometimes I can't.

My box is running Fedora Core 4 and kernel 2.6.14.

I have the following rpms:
python-2.4.1-2
ipython-0.6.15-1.fc4
python-tools-2.4.1-2
python-matplotlib-0.84-1.fc4
python-numeric-23.7-2

Fedora has an out of date ghostscript 7.07, so I installed
ghostscript-8.51from source into /usr/local, but not the fonts, since
they seemed
unnecessary.

As long as I don't use

rc('text', usetex=3DTrue)

I'm ok, but whenever I turn it on, it doesn't work consistently.

Here's some sample code to demonstrate the problem.  If I comment out the r=
c
line, it works fine.

#!/usr/bin/env python

from matplotlib import rc
from matplotlib.numerix import arange, cos, pi
from pylab import *

forces =3D [1, 2, 3, 4]
pofn =3D [.2, .09, .01, .005]

rc('text', usetex=3DTrue)
figure(1)
semilogy(forces,pofn,'k')
xlabel(r'$f_n =3D F_n/\langle F_n \rangle$')
ylabel(r'$P(f_n)$')
axis([0,5,.001,1])

savefig('mtest1.eps')

However, if I run it as is, then I get the following:

[jwlandry@merrimac hopper]$ ./mat-test.py --verbose-helpful
matplotlib data path /usr/share/matplotlib
$HOME=3D/home/jwlandry
CONFIGDIR=3D/home/jwlandry/.matplotlib
loaded rc file /home/jwlandry/.matplotlib/matplotlibrc
matplotlib version 0.84
verbose.level helpful
interactive is False
platform is linux2
numerix Numeric 23.7
font search path ['/usr/share/matplotlib']
loaded ttfcache file /home/jwlandry/.matplotlib/ttffont.cache
backend GTK version 2.6.2

This is dvips(k) 5.95a Copyright 2005 Radical Eye Software (
www.radicaleye.com)
' TeX output 2005.11.25:1645' -> e0dab64d0b15f2821ec713a6e7903ff4.ps
<tex.pro><psfrag.pro><texps.pro><special.pro><color.pro>. <cmr8.pfb>
<cmsy8.pfb><cmsy10.pfb><cmmi8.pfb><cmmi10.pfb><cmr10.pfb>[1
<e0dab64d0b15f2821ec713a6e7903ff4.eps>]

When it doesn't work, a dialog box opens with this message

Save figure failure:
None: Interrupted system call


Help!

James Landry


--
James W. Landry
jwl...@gm...