matplotlib-users Mailing List for matplotlib (Page 6)

> --- Ursprüngliche Nachricht ---
> Von: Darren Dale <dd...@co...>
> An: mat...@li...
> Betreff: Re: [Matplotlib-users] scatter with dots?
> Datum: Thu, 1 Dec 2005 10:37:41 -0500
> 
> 
> I think the draw_markers function already exists for ps, I wrote it up a
> while 
> back, but we ended up masking it when problems arose in the new API.
> 
> Darren
> 
I will look into this. I'm very short on time, so this may take some....
days. 
Drawing markers with postscript procedures seems to me the favorite
solution.
If anyone is interested in that stuff: I found a wonderfull online book: 
'Mathematical Illustrations' from Bill Casselmann.
http://www.math.ubc.ca/~cass/graphics/manual/
It is a postscript book from the mathematical viewpoint.

Regards

Carl

-- 
GMX DSL-Flatrate 1 Jahr kostenlos* + WLAN-Router ab 0,- Euro*
Bis 31.12.2005 einsteigen! Infos unter: http://www.gmx.net/de/go/dsl

Bump...... Anybody.........

On 12/7/05, Charlie Moad <cw...@gm...> wrote:
> How do I force the circle in a widgets.RadioButtons to maintain aspect?
>
> Thanks,
> - Charlie
>

Thanks John, That fixed the problem. 

VJ

----- Original Message ----
From: Alan G Isaac <ai...@am...>
To: mat...@li...
Sent: Wednesday, December 07, 2005 10:38:54 AM
Subject: Re[2]: [Matplotlib-users] Exception after upgrading to 0.85

>     Vinj> I get the following exception after upgrading 
>     from 0.84 to
>     Vinj> 0.85. My server is running on ubuntu with python 2.4:

On Wed, 07 Dec 2005 07:57:23 -0600 John Hunter apparently wrote:
> Try replacing that bit of code with 
>     if iterable(o) and len(o): o = o[0]



Recall a Python 2.4 oddity:

>>> x=[1,2,3,4]
>>> o=iter(x)
>>> len(o)
4
>>> o[0]
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
TypeError: unindexable object

I understand iterables will return to their 2.3 behavior,
but for now we have this oddity.

Cheers,
Alan Isaac






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ok ! solved ! thanks all ! cheers.

2005/12/7, Peter Groszkowski <pgr...@ge...>:
>
>
> > gcc -pthread -fno-strict-aliasing -DNDEBUG -g -O3 -Wall
> > -Wstrict-prototypes -fPIC -Iagg23/include -Isrc -Iswig
> > -I/usr/include/python2.4 -c src/agg.cxx -o
> > build/temp.linux-x86_64-2.4/src/agg.o
> > gcc: installation problem, cannot exec 'cc1plus': No such file or
> > directory
> > error: command 'gcc' failed with exit status 1
> >
> > have you any ideas ?
> >
> looks like you don't have g++ (properly) installed... might want to
> 'apt-get' it...
>
> --
> Peter Groszkowski         Gemini Observatory
> Tel: +1 808 9742509       670 N. A'ohoku Place
> Fax: +1 808 9359235       Hilo, Hawai'i 96720, USA
>
>

Hi,

I want to use matplotlib to generate figures for dynamic website
using a threaded web server. Is matplotlib without any GUI
(i.e. only Agg background)  thread-safe?  Can multiple separate
threads generate figures sumultaneously without problem?

Thanks!
-the.11th

If you have dvipng and set text.usetex : True in your matplotlibrc file, th=
en
xlabel(r'$\rho^2$ along axis') works (and looks darn pretty thanks to Darre=
n).

Ryan

On 12/7/05, Mark Bakker <ma...@gm...> wrote:
> Does anybody know a way to mix mathtext and regular text, for example in =
the
> axis label?
>
>  Something like
>
>  xlabel(r'$\rho^2$ along axis')
>
>  doesn't work. I know this is mentioned in the manual.
>  Just wondering if somebody knows a workaround rather than using the full
> Latex option.
>
>  Thanks, Mark
>

Mark Bakker wrote:
> Something like
> 
> xlabel(r'$\rho^2$ along axis')
> 
> doesn't work. I know this is mentioned in the manual.

Does r'$\rho^2 \text{along axis}'

work/ I have no idea if it should, but that's how it's done in an 
equation environment in LaTeX.

-Chris


-- 
Christopher Barker, Ph.D.
Oceanographer
                                     		
NOAA/OR&R/HAZMAT         (206) 526-6959   voice
7600 Sand Point Way NE   (206) 526-6329   fax
Seattle, WA  98115       (206) 526-6317   main reception

Chr...@no...

> gcc -pthread -fno-strict-aliasing -DNDEBUG -g -O3 -Wall
> -Wstrict-prototypes -fPIC -Iagg23/include -Isrc -Iswig
> -I/usr/include/python2.4 -c src/agg.cxx -o
> build/temp.linux-x86_64-2.4/src/agg.o
> gcc: installation problem, cannot exec 'cc1plus': No such file or 
> directory
> error: command 'gcc' failed with exit status 1
>
> have you any ideas ?
>
looks like you don't have g++ (properly) installed... might want to 
'apt-get' it...

-- 
Peter Groszkowski         Gemini Observatory
Tel: +1 808 9742509       670 N. A'ohoku Place
Fax: +1 808 9359235       Hilo, Hawai'i 96720, USA 

Sorry, for wasting your time... I figure it out easily.

Bill Dandreta wrote:
>Do you have pygtk installed?

This is of course the appropriate question and the answer is: "I 've
installed wxPython!" So, I changed GTKAgg to WXAgg in the matplotlibrc and
now it works... ;-)

cheers

Jens B.

Darren Dale wrote:
> On Wednesday 07 December 2005 10:51, Christian Kristukat wrote:
> 
>>I see. Thanks for the explanation. Your code seems to export both an eps
>>and pdf file, right? Anyway, I don't have the program ps2eps on my system
>>so I'll remove that part.
> 
> 
> Dont let that stand in your way:
> http://www.tm.uka.de/~bless/ps2eps

You're right. That's worth having.
Thank you again for your hints.
Christian

On Wednesday 07 December 2005 10:51, Christian Kristukat wrote:
> I see. Thanks for the explanation. Your code seems to export both an eps
> and pdf file, right? Anyway, I don't have the program ps2eps on my system
> so I'll remove that part.

Dont let that stand in your way:
http://www.tm.uka.de/~bless/ps2eps

Darren Dale wrote:
> On Wednesday 07 December 2005 08:41, Christian Kristukat wrote:
> 
>>Darren Dale wrote:
>>
>>>On Tuesday 06 December 2005 10:03, Christian Kristukat wrote:
>>>
>>>>Darren Dale wrote:
>>>>
>>>>>On Tuesday 06 December 2005 09:10, Alex Gontmakher wrote:
>>>>>
>>>>>>Hi,
>>>>>>
>>>>>>I'm trying to use matplotlib solely for my plotting needs.
>>>>>>Problem is, the fonts are embedded in each EPS file, and
>>>>>>when I import several plots (I have tens of them...) into a
>>>>>>single Latex, the resulting file is HUGE.
>>>>>>
>>>>>>Any suggestions?
>>>>>
>>>>>There are currently two options: you can either set ps.useafm = True, or
>>>>>you can set text.usetex = True in your rc settings. Since you are
>>>>>importing figures into latex, I suggest the usetex option. That way,
>>>>>your figure fonts can be the same as your text fonts. You'll take a bit
>>>>>of a speed hit with the latter option, but in my opinion, its the only
>>>>>way to go for generating plots for publication.
>>>>
>>>>When using tex for font rendering I noticed that parts of the text are
>>>>not converted to polygons but embedded as bitmaps. That makes the files
>>>>big again. Do you now how to avoid that? E.g. using the r'$C_{12}$ will
>>>>produce two images for the numbers and a polygon for the 'C'.
>>>
>>>I made a wiki entry a while back about how to work around this problem,
>>>but it looks like someone deleted it in mid-November, and I dont have a
>>>backup copy. My solution requires ghostview and xpdf, which is why we
>>>dont include it in mpl by default.
>>
>>Thanks!
>>Has using pdflatex for tex labels been considered? Or is that too much
>>dependency? It could possibly even be faster.
> 
> 
> I'm guessing pdflatex is provided by default by every up-to-date latex 
> installation out there. However, mpl uses a latex package called PSFrag to 
> render the text in an intermediate postscript file, which is not compatible 
> with pdflatex. Unfortunately, if you embed that intermediate postscript file 
> in a new document, the text will frequently be upside down, because PSFrag 
> uses some commands that are illegal in embedded documents. So by default, mpl 
> uses ghostscript to "distill" the intermediate postscript file, converting 
> the fonts to outlines and circumventing the problem.
> 
> The code I posted last time replaces the distilling step with a ridiculous 
> renormalization step (converting the file to pdf using ghostscript, and then 
> converting back to eps using xpdf) which generates a new eps file that can be 
> embedded in another document. This seems to be pretty robust, convoluted 
> though it is. I generated all the figures in my dissertation this way.

I see. Thanks for the explanation. Your code seems to export both an eps and pdf
file, right? Anyway, I don't have the program ps2eps on my system so I'll remove
that part.

> A side note, if you intend to compile a document with pdflatex, you can 
> convert mpl's eps files with epstopdf, which is included in recent versions 
> of TeTeX.

That's the way I do it, too. But there's always a polygon at the left bottom
corner of a letter page which makes the bbox large. It's too annoying to set the
bbox by hand so Iusually convert the .eps to .sk with pstoedit, edit it with
skencil, print it as eps and convert it to pdf. I'd be happy if some of those
steps would vanish in future.

Regards, Christian

>     Vinj> I get the following exception after upgrading 
>     from 0.84 to
>     Vinj> 0.85. My server is running on ubuntu with python 2.4:

On Wed, 07 Dec 2005 07:57:23 -0600 John Hunter apparently wrote:
> Try replacing that bit of code with 
>     if iterable(o) and len(o): o = o[0]



Recall a Python 2.4 oddity:

>>> x=[1,2,3,4]
>>> o=iter(x)
>>> len(o)
4
>>> o[0]
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
TypeError: unindexable object

I understand iterables will return to their 2.3 behavior,
but for now we have this oddity.

Cheers,
Alan Isaac

On Wed, 7 Dec 2005, Mark Bakker apparently wrote:=20
> xlabel(r'$\rho^2$ along axis')

Don't have time to test now, but do I recall that \text is=20
implemented ->
xlabel(r'$\rho^2 \text{ along axis}$')=20

Cheers,
Alan Isaac

How do I force the circle in a widgets.RadioButtons to maintain aspect?

Thanks,
- Charlie

Hi list,

After successful installation of wxGTK, wxPython and matplotlib I tried the
"simple_plot.py example" wich I 've found in the faq. But I 'm running into
trouble:

jens-ifw@x21lx-jensb:~/Documents/Python> python simple_plot.py
--verbose-helpful matplotlib data path /usr/local/share/matplotlib
$HOME=/home/jens-ifw CONFIGDIR=/home/jens-ifw/.matplotlib
loaded rc file /usr/local/share/matplotlib/matplotlibrc
matplotlib version 0.85
verbose.level helpful
interactive is False
platform is linux2
numerix Numeric 24.0
font search path ['/usr/local/share/matplotlib'] loaded ttfcache file
/home/jens-ifw/.matplotlib/ttffont.cache
Traceback (most recent call last):
  File "simple_plot.py", line 3, in ?
    from pylab import *
  File "/usr/local/lib/python2.4/site-packages/pylab.py", line 1, in ?
    from matplotlib.pylab import *
  File "/usr/local/lib/python2.4/site-packages/matplotlib/pylab.py", line
217, in ?
    new_figure_manager, draw_if_interactive, show = pylab_setup()
  File
"/usr/local/lib/python2.4/site-packages/matplotlib/backends/__init__.py",
line 24, in pylab_setup
    globals(),locals(),[backend_name])
  File
"/usr/local/lib/python2.4/site-packages/matplotlib/backends/backend_gtkagg.p
y", line 10, in ?
    from backend_gtk import gtk, FigureManagerGTK, FigureCanvasGTK,\
  File
"/usr/local/lib/python2.4/site-packages/matplotlib/backends/backend_gtk.py",
line 6, in ?
    import gobject
ImportError: No module named gobject

Do I have to build wxPython with BUILD_GLCANVAS=1? Or what else could be
wrong in the configuration? Thank 's in advance...

cheers

Jens B.

Hi list,
I'm working in matplotlib OO mode.

I first create an instance of Subplot(): a = Subplot(f,111) with f an 
existing figure.
I plot some basic data using a.plot([1,2,3])
Then i add this subplot to the figure with the method f2.add_subplot(a).
The subplot is well displayed in the figure.

But my problem is i can't zoom on the figure. Xlabel and YLabel are 
redrawn but no the subplot.

Can anybody give me a solution please?
I need to create separately the figure and the subplot.

Thanks a lot,
Philippe Collet

On Wednesday 07 December 2005 08:41, Christian Kristukat wrote:
> Darren Dale wrote:
> > On Tuesday 06 December 2005 10:03, Christian Kristukat wrote:
> >>Darren Dale wrote:
> >>>On Tuesday 06 December 2005 09:10, Alex Gontmakher wrote:
> >>>>Hi,
> >>>>
> >>>>I'm trying to use matplotlib solely for my plotting needs.
> >>>>Problem is, the fonts are embedded in each EPS file, and
> >>>>when I import several plots (I have tens of them...) into a
> >>>>single Latex, the resulting file is HUGE.
> >>>>
> >>>>Any suggestions?
> >>>
> >>>There are currently two options: you can either set ps.useafm = True, or
> >>>you can set text.usetex = True in your rc settings. Since you are
> >>>importing figures into latex, I suggest the usetex option. That way,
> >>> your figure fonts can be the same as your text fonts. You'll take a bit
> >>> of a speed hit with the latter option, but in my opinion, its the only
> >>> way to go for generating plots for publication.
> >>
> >>When using tex for font rendering I noticed that parts of the text are
> >> not converted to polygons but embedded as bitmaps. That makes the files
> >> big again. Do you now how to avoid that? E.g. using the r'$C_{12}$ will
> >> produce two images for the numbers and a polygon for the 'C'.
> >
> > I made a wiki entry a while back about how to work around this problem,
> > but it looks like someone deleted it in mid-November, and I dont have a
> > backup copy. My solution requires ghostview and xpdf, which is why we
> > dont include it in mpl by default.
>
> Thanks!
> Has using pdflatex for tex labels been considered? Or is that too much
> dependency? It could possibly even be faster.

I'm guessing pdflatex is provided by default by every up-to-date latex 
installation out there. However, mpl uses a latex package called PSFrag to 
render the text in an intermediate postscript file, which is not compatible 
with pdflatex. Unfortunately, if you embed that intermediate postscript file 
in a new document, the text will frequently be upside down, because PSFrag 
uses some commands that are illegal in embedded documents. So by default, mpl 
uses ghostscript to "distill" the intermediate postscript file, converting 
the fonts to outlines and circumventing the problem.

The code I posted last time replaces the distilling step with a ridiculous 
renormalization step (converting the file to pdf using ghostscript, and then 
converting back to eps using xpdf) which generates a new eps file that can be 
embedded in another document. This seems to be pretty robust, convoluted 
though it is. I generated all the figures in my dissertation this way.

A side note, if you intend to compile a document with pdflatex, you can 
convert mpl's eps files with epstopdf, which is included in recent versions 
of TeTeX.

Darren

>>>>> "Vinj" == Vinj Vinj <vin...@ya...> writes:

    Vinj> I get the following exception after upgrading from 0.84 to
    Vinj> 0.85. My server is running on ubuntu with python 2.4:

Try replacing that bit of code with

    if iterable(o) and len(o): o = o[0]

JDH

Darren Dale wrote:
> On Tuesday 06 December 2005 10:03, Christian Kristukat wrote:
> 
>>Darren Dale wrote:
>>
>>>On Tuesday 06 December 2005 09:10, Alex Gontmakher wrote:
>>>
>>>>Hi,
>>>>
>>>>I'm trying to use matplotlib solely for my plotting needs.
>>>>Problem is, the fonts are embedded in each EPS file, and
>>>>when I import several plots (I have tens of them...) into a
>>>>single Latex, the resulting file is HUGE.
>>>>
>>>>Any suggestions?
>>>
>>>There are currently two options: you can either set ps.useafm = True, or
>>>you can set text.usetex = True in your rc settings. Since you are
>>>importing figures into latex, I suggest the usetex option. That way, your
>>>figure fonts can be the same as your text fonts. You'll take a bit of a
>>>speed hit with the latter option, but in my opinion, its the only way to
>>>go for generating plots for publication.
>>
>>When using tex for font rendering I noticed that parts of the text are not
>>converted to polygons but embedded as bitmaps. That makes the files big
>>again. Do you now how to avoid that? E.g. using the r'$C_{12}$ will produce
>>two images for the numbers and a polygon for the 'C'.
> 
> 
> I made a wiki entry a while back about how to work around this problem, but it 
> looks like someone deleted it in mid-November, and I dont have a backup copy.
> My solution requires ghostview and xpdf, which is why we dont include it in 
> mpl by default.

Thanks!
Has using pdflatex for tex labels been considered? Or is that too much
dependency? It could possibly even be faster.

Christian

Does anybody know a way to mix mathtext and regular text, for example in th=
e
axis label?

Something like

xlabel(r'$\rho^2$ along axis')

doesn't work. I know this is mentioned in the manual.
Just wondering if somebody knows a workaround rather than using the full
Latex option.

Thanks, Mark

I get the following exception after upgrading from 0.84 to 0.85. My server is running on ubuntu with python 2.4:

setp(axMiddle.get_xticklabels(), rotation=45, horizontalalignment='right', fontsize=7)
  File "/usr/lib/python2.4/site-packages/matplotlib/pylab.py", line 1551, in setp
    ret = _setp(*args, **kwargs)
  File "/usr/lib/python2.4/site-packages/matplotlib/artist.py", line 468, in setp
    insp = ArtistInspector(h)
  File "/usr/lib/python2.4/site-packages/matplotlib/artist.py", line 260, in __init__
    if iterable(o): o = o[0]
 IndexError: list index out of range

any help would be appreciated.

VJ

On Tuesday 06 December 2005 10:03, Christian Kristukat wrote:
> Darren Dale wrote:
> > On Tuesday 06 December 2005 09:10, Alex Gontmakher wrote:
> >>Hi,
> >>
> >>I'm trying to use matplotlib solely for my plotting needs.
> >>Problem is, the fonts are embedded in each EPS file, and
> >>when I import several plots (I have tens of them...) into a
> >>single Latex, the resulting file is HUGE.
> >>
> >>Any suggestions?
> >
> > There are currently two options: you can either set ps.useafm = True, or
> > you can set text.usetex = True in your rc settings. Since you are
> > importing figures into latex, I suggest the usetex option. That way, your
> > figure fonts can be the same as your text fonts. You'll take a bit of a
> > speed hit with the latter option, but in my opinion, its the only way to
> > go for generating plots for publication.
>
> When using tex for font rendering I noticed that parts of the text are not
> converted to polygons but embedded as bitmaps. That makes the files big
> again. Do you now how to avoid that? E.g. using the r'$C_{12}$ will produce
> two images for the numbers and a polygon for the 'C'.

I made a wiki entry a while back about how to work around this problem, but it 
looks like someone deleted it in mid-November, and I dont have a backup copy.
My solution requires ghostview and xpdf, which is why we dont include it in 
mpl by default.

You can remove the following block in backend_ps.py, starting around line 
1144:

            command = 'latex -interaction=nonstopmode "%s"' % texfile

            verbose.report(command, 'debug-annoying')
            stdin, stdout, stderr = os.popen3(command)
            verbose.report(stdout.read(), 'debug-annoying')
            verbose.report(stderr.read(), 'helpful')
            command = 'dvips -R -T %fin,%fin -o "%s" "%s"' % (pw, ph, psfile, 
dvifile)
            verbose.report(command, 'debug-annoying')
            stdin, stdout, stderr = os.popen3(command)
            verbose.report(stdout.read(), 'debug-annoying')
            verbose.report(stderr.read(), 'helpful')
            os.remove(epsfile)
            if ext.startswith('.ep'):
                dpi = rcParams['ps.distiller.res']

                if sys.platform == 'win32':
                    command = 'gswin32c -dBATCH -dNOPAUSE -dSAFER -r%d \
                      -sDEVICE=epswrite -dLanguageLevel=2 -dEPSFitPage \
                      -sOutputFile="%s" "%s"'% (dpi, epsfile, psfile)
                else:
                    command = 'gs -dBATCH -dNOPAUSE -dSAFER -r%d \
                    -sDEVICE=epswrite -dLanguageLevel=2 -dEPSFitPage \
                    -sOutputFile="%s" "%s"'% (dpi, epsfile, psfile)

                verbose.report(command, 'debug-annoying')
                stdin, stdout, stderr = os.popen3(command)
                verbose.report(stdout.read(), 'debug-annoying')
                verbose.report(stderr.read(), 'helpful')
                shutil.move(epsfile, outfile)
            else: shutil.move(psfile, outfile)


and replace it with this:

            command = 'latex -interaction=nonstopmode "%s"' % texfile
            verbose.report(command, 'debug-annoying')
            stdin, stdout, stderr = os.popen3(command)
            verbose.report(stdout.read(), 'debug-annoying')
            verbose.report(stderr.read(), 'helpful')
            command = 'dvips -R -T %fin,%fin -o "%s" "%s"' % (pw, ph, psfile, 
dvifile)
            verbose.report(command, 'debug-annoying')
            stdin, stdout, stderr = os.popen3(command)
            verbose.report(stdout.read(), 'debug-annoying')
            verbose.report(stderr.read(), 'helpful')
            os.remove(epsfile)
            pdffile = tmpname + '.pdf'
            if ext.startswith('.ep'):
                command = 'ps2pdf "%s"'% psfile
                os.system(command)
                command = 'pdftops -level2 "%s" "%s"'% (pdffile, psfile)
                os.system(command)
                os.remove(pdffile)
                command = '/usr/local/bin/ps2eps -l "%s"'% psfile
                stdin, stderr = os.popen4(command)
                verbose.report(stderr.read(), 'helpful')
                command = 'epstopdf "%s"'% epsfile
                os.system(command)
                shutil.move(epsfile, outfile)
                shutil.move(pdffile, basename+'.pdf')
            else:
                command = 'ps2pdf "%s" "%s"'% (psfile, pdffile)
                stdin, stderr = os.popen4(command)
                verbose.report(stderr.read(), 'helpful')
                os.remove(psfile)
                command = 'pdftops -paperw %d -paperh %d -level2 "%s" "%s"'% \
                            (int(pw*72), int(ph*72), pdffile, psfile)
                os.system(command)
                shutil.move(psfile, outfile)

Darren

hi,

i'm triing to install matplotlib with ubuntu breezy
(amd64). An error occurs with 'python setup.py build' :

gcc -pthread -fno-strict-aliasing -DNDEBUG -g -O3 -Wall
-Wstrict-prototypes -fPIC -Iagg23/include -Isrc -Iswig
-I/usr/include/python2.4 -c src/agg.cxx -o
build/temp.linux-x86_64-2.4/src/agg.o
gcc: installation problem, cannot exec 'cc1plus': No such file or directory
error: command 'gcc' failed with exit status 1

have you any ideas ?

thanks.

mmanu

Darren Dale wrote:
> On Tuesday 06 December 2005 09:10, Alex Gontmakher wrote:
> 
>>Hi,
>>
>>I'm trying to use matplotlib solely for my plotting needs.
>>Problem is, the fonts are embedded in each EPS file, and
>>when I import several plots (I have tens of them...) into a
>>single Latex, the resulting file is HUGE.
>>
>>Any suggestions?
> 
> 
> There are currently two options: you can either set ps.useafm = True, or you 
> can set text.usetex = True in your rc settings. Since you are importing 
> figures into latex, I suggest the usetex option. That way, your figure fonts 
> can be the same as your text fonts. You'll take a bit of a speed hit with the 
> latter option, but in my opinion, its the only way to go for generating plots 
> for publication.

When using tex for font rendering I noticed that parts of the text are not
converted to polygons but embedded as bitmaps. That makes the files big again.
Do you now how to avoid that? E.g. using the r'$C_{12}$ will produce two images
for the numbers and a polygon for the 'C'.

Regards, Christian