matplotlib-users Mailing List for matplotlib

This is the second bug fix release of the 0.83 series, but a couple of
new features have crept in.... The notes below include all new
features in 0.83; I've just been a little slow getting them typed up
:-)
You can read these with links at
http://matplotlib.sourceforge.net/whats_new.html
What's new in matplotlib 0.83
axis('scale')
 Added Mark Athen's 'scale' patch, so that on a scaled axis a circle
 looks like circle. See help(axis).
New cursor and span selector widgets
 Added new Cursor and HorizontalSpanSelector to
 matplotlib.widgets. See examples/widgets/cursor.py and
 examples/widgets/span_selector.py. Set useblit = True on gtkagg for
 significantly enhanced performance.
draw events
 You can use use matplotlib event handling to register a callback
 after figure draw using 'draw_event' which calls the callback with a
 DrawEvent instance
 def callback(event):
 #event.renderer is the backend Renderer instance
 pass
 connect('draw_event')
Full screen mode in GTK*
 Use 'f' to toggle full screen mode in the GTK backends. 
GTK and SVG fixes
 Steve Chaplin has made numerous updates to the GTK and SVG
 backends. See the CHANGELOG for details.
Reorganized config files
 Made HOME/.matplotlib the new config dir where the matplotlibrc
 file, the ttf.cache, and the tex.cache live. The new default
 filenames in .matplotlib have no leading dot and are not hidden. Eg,
 the new names are matplotlibrc, tex.cache, and ttffont.cache. This
 is how ipython does it so it must be right. If old files are found,
 a warning is issued and they are moved to the new location. Also
 fixed texmanager to put all files, including temp files in
 ~/.matplotlib/tex.cache, which allows you to usetex in non-writable
 dirs.
Using matplotlib.agg to draw paths
 Updated agg_test.py to demonstrate curved paths and fills.
CocoaAgg
 New CocoaAgg backend for native GUI on OSX, 10.3 and 10.4 compliant.
Qt enhancements
 Applied Ted Drain's QtAgg patch: 1) Changed the toolbar to be a
 horizontal bar of push buttons instead of a QToolbar and updated the
 layout algorithms in the main window accordingly. This eliminates
 the ability to drag and drop the toolbar and detach it from the
 window. 2) Updated the resize algorithm in the main window to show
 the correct size for the plot widget as requested. This works almost
 correctly right now. It looks to me like the final size of the
 widget is off by the border of the main window but I haven't figured
 out a way to get that information yet. We could just add a small
 margin to the new size but that seems a little hacky. 3) Changed the
 x/y location label to be in the toolbar like the Tk backend instead
 of as a status line at the bottom of the widget. 4) Changed the
 toolbar pixmaps to use the ppm files instead of the png files. I
 noticed that the Tk backend buttons looked much nicer and it uses
 the ppm files so I switched them.
mathtext optimizations
 Upgraded pyparsing and applied Paul McGuire's suggestions for
 speeding things up. This more than doubles the speed of mathtext in
 my simple tests.
Bugs fixed / small features 
 Applied SF patches 1242648, 1244732. Fixes SF bugs 1238412, 1231611,
 1209354, subplot (2,1,1) bug,
Downloads at http://matplotlib.sourceforge.net

I understand that Numeric and Numarray operate as Numerix within
matplotlib. If I am running AXAgg as a backend and I'm importing and
using Numeric, will this produce a conflict or any problems? Should I
only use Numerix?
Thanks,
Jeff 

On Friday 29 July 2005 10:02 am, John Hunter wrote:
> >>>>> "Darren" == Darren Dale <dd...@co...> writes:
>
> Darren> Just to get the ball rolling (and because I couldnt sleep
> Darren> this morning), I made a page discussing TeX/LaTeX with
> Darren> mpl.
>
> Darren> http://www.scipy.org/Members/dsdale/textwithlatex/document_view
>
> Great -- that is very useful. You may want to mention the dvipng
> requirement....
>
> Darren> How do I submit this so it can be found from the
> Darren> MatplotlibCookbook website?
>
> Go to the cookbook page and add a link to it in the "Recipes" list.
>
> I think it would be nice to have all the recipes live as children of
> MatplotlibCookbook, so you may need to "reparent" your page (see the
> form at the bottom of the each wiki page) or if this doesn't work
> create a new blank page from the cookbook main page and just paste
> your entry in. I'm a bit of a scipy wiki newbie so I am not sure
> about all the details.
Just to be clear, I was completely uninitiated in working with wikis, so this 
seemed more difficult at first than it really is. 
I just added a comment to the MatplotlibCookbook page explaining how to add a 
new page. Its really a piece of cake.
-- 
Darren

On 2005年7月29日, Dimitri D'Or apparently wrote: 
> I have a two-dimensional array from which I wish to 
> compute the gradient (i.e. the slope against the first and 
> second dimension). With Matlab, I can do it easily using 
> the gradient.m function. Is there something similar in 
> Scipy or matplotlib? I've browsed the documentation but 
> couldn't found anything but approximate gradient 
> computations on functions in the optimize module. Nothing 
> about computations on matrices. 
Look at scipy.diff.
E.g., for the two dimensions
grad0=scipy.diff(x,axis=0)
grad1=scipy.diff(x,axis=1)
hth,
Alan Isaac

> That's very good bet -- 2.95 is *really old*. It looks like it may
> not be properly handling wide characters. I don't think there is
> anything we can do on our end about this one. Can you upgrade your
> compiler?
Well, it's an old server box of my faculty at the university. I'll see what 
I can do about it.
Thanks for your advice.
Sascha 

There's a matplotlib cheat sheet for IDL users as Appendix D of the 
recently posted tutorial
on using Python for data analysis in astronomy.
http://www.scipy.org/wikis/topical_software/Tutorial
http://stsdas.stsci.edu/perry/pydatatut.pdf
The tutorial PDF document is rather large; appendix D runs from pages 
128-135.
Maybe we'll split it off into a separate document and post it on the new 
matplotlib wiki.
Vicki Laidler
>===== Original message from Alan G. Isaac | 2005年7月28日:
> 
>
>>> More natural choices might be 
>>> - GAUSS - PDL - SciLab - Lush - Yorick - Algae - A+
>> 
>>
>
>thanks for the input.
>how different are PDL, IDL and GDL?
>aren't there a PyDL or pyIDL also?
>or is this something different?
>
>this resource might be useful for this, i guess?
>"IDL to Numeric/numarray Mapping"
>http://www.johnny-lin.com/cdat_tips/tips_array/idl2num.html
>

>>>>> "Steve" == Steve Schmerler <el...@gm...> writes:
 Steve> Hi Well if you do lineplots
 Steve> 	# plot some lines x = [1,2,3] for i in range(...):
 Steve> plot(x)
 Steve> mpl changes the color of each line which doesn't happen in
 Steve> the case of marker plots.
Actually something different is going on, but I had to grok through
matplotlib.axes._process_plot_var_args to figure it out.
The default color cycling happens when there is no string format
applied, and is independent of markers and lines. For example, the
following does not cycle either
for i in range(4):
 plot(rand(5), rand(5), '-')
because a format string is applied. 
You can make markers cycle too w/o a form string by changing the rc
params so that the default makrer is not 'None'
 rcParams['lines.marker'] = 'o'
 rcParams['lines.linestyle'] = 'None'
 for i in range(4):
 plot(rand(5), rand(5))
Whether or not this is ideal behavior is debatable. But it is
probably good enough since it is easy enough to force plot to act like
you want by explicitly passing args, as you did. I think Niklas'
suggestion of explicitly passing the kwargs for marker, linestyle,
color, markerfacecolor and so on is a better approach than
constructing arcane format strings. It is more readable and more
flexible, because format strings limit you to a small set of colors
whereas the kwargs approach supports arbitrary color arguments.
JDH

>>>>> "Darren" == Darren Dale <dd...@co...> writes:
 Darren> Just to get the ball rolling (and because I couldnt sleep
 Darren> this morning), I made a page discussing TeX/LaTeX with
 Darren> mpl.
 Darren> http://www.scipy.org/Members/dsdale/textwithlatex/document_view
Great -- that is very useful. You may want to mention the dvipng
requirement....
 Darren> How do I submit this so it can be found from the
 Darren> MatplotlibCookbook website?
Go to the cookbook page and add a link to it in the "Recipes" list. 
I think it would be nice to have all the recipes live as children of
MatplotlibCookbook, so you may need to "reparent" your page (see the
form at the bottom of the each wiki page) or if this doesn't work
create a new blank page from the cookbook main page and just paste
your entry in. I'm a bit of a scipy wiki newbie so I am not sure
about all the details.
Cheers,
JDH

>>>>> "Sascha" == Sascha GL <Sas...@gm...> writes:
 Sascha> I am having issues installing matplotlib on a Linux box:
 Sascha> gcc -pthread -fno-strict-aliasing -DNDEBUG -g -O3 -Wall
 Sascha> -Wstrict-prototypes -fPIC -Isrc -I. -I/usr/local/include
 Sascha> -I/usr/include -I/opt/Python-2.3.5/Include
 Sascha> -I/opt/Python-2.3.5 -c CXX/cxx_extensions.cxx -o
 Sascha> build/temp.linux-i686-2.3/cxx_extensions.o -DNUMERIC=1 In
 Sascha> file included from CXX/Extensions.hxx:18, from
 Sascha> CXX/cxx_extensions.cxx:1: /usr/include/g++/std/bastring.h:
 Sascha> In method `const Py_UNICODE * basic_string<short unsigned
 Sascha> int,string_char_traits<short unsigned
 int> ,__default_alloc_template<true,0> >::c_str() const':
 Sascha> CXX/Objects.hxx:1505: instantiated from here
 Sascha> /usr/include/g++/std/bastring.h:338: return to `const
 Sascha> Py_UNICODE *' from `const char *' error: command 'gcc'
 Sascha> failed with exit status 1
 Sascha> I can't see what's missing or whatever else is
 Sascha> wrong... any idea? Could it be that the gcc version (2.95)
 Sascha> is too old?
That's very good bet -- 2.95 is *really old*. It looks like it may
not be properly handling wide characters. I don't think there is
anything we can do on our end about this one. Can you upgrade your
compiler?
JDH

On Thursday 28 July 2005 03:57 pm, John Hunter wrote:
> I created a wiki page on the scipy web site for people to upload tips,
> tricks, HOWTOs and recipes for matplotlib. Everyone is encouraged to
> contribute; you just need to get a login for the scipy page from
> http://www.scipy.org/wikis/topical_software/join_form .
>
> One easy way to contribute is to take a file from the examples
> directory and explain and annotate it and place it on the wiki. You
> can also upload images to show off your work. Beyond that, everything
> is fair game: from a tutorial freezing mpl with py2exe to embedding
> mpl in your favorite GUI to doing animations.
>
> To get the ball rolling, I cleaned up my last post to the mailing list
> and posted it with a screenshot
>
> http://www.scipy.org/wikis/topical_software/MatplotlibCookbook
>
> Thanks to scipy.org and enthought for hosting!
Just to get the ball rolling (and because I couldnt sleep this morning), I 
made a page discussing TeX/LaTeX with mpl.
http://www.scipy.org/Members/dsdale/textwithlatex/document_view
How do I submit this so it can be found from the MatplotlibCookbook website?
-- 
Darren

I am having issues installing matplotlib on a Linux box:
gcc -pthread -fno-strict-aliasing -DNDEBUG -g -O3 -Wall -Wstrict-prototypes
-fPIC -Isrc -I. -I/usr/local/include -I/usr/include
-I/opt/Python-2.3.5/Include -I/opt/Python-2.3.5 -c CXX/cxx_extensions.cxx -o
build/temp.linux-i686-2.3/cxx_extensions.o -DNUMERIC=1
In file included from CXX/Extensions.hxx:18,
 from CXX/cxx_extensions.cxx:1:
/usr/include/g++/std/bastring.h: In method `const Py_UNICODE *
basic_string<short unsigned int,string_char_traits<short unsigned
int>,__default_alloc_template<true,0> >::c_str() const':
CXX/Objects.hxx:1505: instantiated from here
/usr/include/g++/std/bastring.h:338: return to `const Py_UNICODE *' from
`const char *'
error: command 'gcc' failed with exit status 1
I can't see what's missing or whatever else is wrong... any idea? Could it
be that the gcc version (2.95) is too old?
Thanks,
Sascha
-- 
5 GB Mailbox, 50 FreeSMS http://www.gmx.net/de/go/promail
+++ GMX - die erste Adresse für Mail, Message, More +++

Hi all,
 
I have a two-dimensional array from which I wish to compute the gradient
(i.e. the slope against the first and second dimension). With Matlab, I can
do it easily using the gradient.m function. Is there something similar in
Scipy or matplotlib? I've browsed the documentation but couldn't found
anything but approximate gradient computations on functions in the optimize
module. Nothing about computations on matrices.
 
Thank you for your help,
 
Dimitri
 

Hi
Well if you do lineplots
	# plot some lines
	x = [1,2,3]
	for i in range(...):
		plot(x)
mpl changes the color of each line which doesn't happen in the case of
marker plots.
cheers,
steve
N. Volbers wrote:
> Hello Steve,
> 
> Steve Schmerler schrieb:
> 
>> Is there another way to cycle through colors when repeating marker plots
>> except
>>
>> c = 'bgrcmykw'
>> for i in range(...):
>> plot(..., '+-' + c[i])
> 
> 
> You can of course specify the line properties via the keyword arguments 
> 'linestyle', 'marker' and in this case 'color'.
> Since the kind of cycling you showed above is a good and working way, 
> maybe you can explain in more detail what you are looking for.
> 
> Best regards,
> 
> Niklas Volbers.
> 
> 

Hello Steve,
Steve Schmerler schrieb:
> Is there another way to cycle through colors when repeating marker plots
> except
>
> c = 'bgrcmykw'
> for i in range(...):
> plot(..., '+-' + c[i])
You can of course specify the line properties via the keyword arguments 
'linestyle', 'marker' and in this case 'color'. 
Since the kind of cycling you showed above is a good and working way, 
maybe you can explain in more detail what you are looking for.
Best regards,
Niklas Volbers.