matplotlib-users — Discussion related to using matplotlib

Re: [Matplotlib-users] Animated plot wth GTKagg

[Arnd B. <arn...@we...>]

Hi,

On Wed, 5 Jan 2005, Ben Vanhaeren wrote:

> Hello,
>
> I'm trying to generate an animated plot embedded in gtk. The problem I have is
> that the plot only gets drawn when the animation loop is finished instead of
> everytime the draw() function is called inside the loop. Is there any other
> way to force the plot to be redrawn ?

From your description I suspect that you have a loop in
a subroutine which does one plot after another. However,
doing it this way does not leave gtk any opportunity to
refresh the corresponding window.
In the example of a moving sine
  http://matplotlib.sourceforge.net/examples/anim.py
John remarks that one has to
"""
# turn interactive mode on for dynamic updates.  If you aren't in
# interactive mode, you'll need to use a GUI event handler/timer.
"""

Maybe you can use something from the mov_sin_mpl_gtk.py example,
http://sourceforge.net/mailarchive/forum.php?thread_id=6175425&forum_id=33405

I for myself haven't use embedding in gtk, so maybe someone
else has a working example...

Best,

Arnd

[Matplotlib-users] Animated plot wth GTKagg

[Ben V. <bva...@sc...>]

Hello,

I'm trying to generate an animated plot embedded in gtk. The problem I have is 
that the plot only gets drawn when the animation loop is finished instead of 
everytime the draw() function is called inside the loop. Is there any other 
way to force the plot to be redrawn ?

Best regards,

Ben Vanhaeren    

[Matplotlib-users] CONFUSION over meaning of 'shape' parameter of arrays for pcolor plot

[<seb...@sp...>]

I'm getting confused about meaning of shape parameter
of arrays used in a pcolor plot...

xarray= [ 0.    1.25  2.5   3.75  5.    0.    1.25  2.5   3.75  5.
0.    1.25  2 .5
         3.75  5.    0.    1.25  2.5   3.75  5.  ]
yarray= [500 500 500 500 500 600 600 600 600 600 700 700 700 700 700
800 800 800 80 0
      800]
zarray= [...etc.]

This will create a proper pcolor plot with 4 rows and 5 columns
if I set all 3 array 'shapes' to be (4, 5).

What is confusing me is that if I want to SWAP xarray and yarray
in order to create a plot with 5 rows and 4 columns then
I MUST STILL SET 'shapes' TO BE (4,5).

'shapes' OF ARRAYS DOESN'T EQUAL DIMENSIONS OF PLOT!?!?
*This* is what is confusing me.  I'm not sure what array 'shape'
means if it doesn't mean (# plot rows, # plot columns).

Any help greatly appreciated.

Sincerely,

Chris




--
_______________________________________

Christian Seberino, Ph.D.
SPAWAR Systems Center San Diego
Code 2872
49258 Mills Street, Room 158
San Diego, CA 92152-5385
U.S.A.

Phone: (619) 553-9973
Fax  : (619) 553-6521
Email: seb...@sp...
_______________________________________

[Matplotlib-users] any concerns with pcolor (x,y,z) points 1. not being regular lattice 2. in random order?

[<seb...@sp...>]

pcolor function gives a nice color plot when user supplies
a list of triplets.  e.g. [ (1,2,3), (4,5,6), ... ].

I usually try to supply these points such that the points
are in some *order* and on a regular *lattice*.

Are there any issues with supplying points in any random
order that aren't evenly spaced but completely random
in position as well?

Chris
--
_______________________________________

Christian Seberino, Ph.D.
SPAWAR Systems Center San Diego
Code 2872
49258 Mills Street, Room 158
San Diego, CA 92152-5385
U.S.A.

Phone: (619) 553-9973
Fax  : (619) 553-6521
Email: seb...@sp...
_______________________________________

Re: [Matplotlib-users] Building on fedora3?

[Stephen W. <ste...@cs...>]

Fernando Perez wrote:

> I was getting a 'pygtk present but import failed' message, which I 
> couldn't understand.  I modified setup.py to reraise the exception at 
> that point, and it turned out to be a RuntimeError('could not open 
> display') exception.

Yes, I noticed the same thing when I tried to build matplotlib through 
an SSH session which didn't have X forwarding enabled.  I get the 
message "pygtk present but import failed
Using default library and include directories for Tcl and Tk because a 
Tk window failed to open.  You may need to define DISPLAY for Tk to work 
so that setup can determine where your libraries are located."  The code 
is in setupext.py starting at line 198:

    try:
        tk=Tkinter.Tk()
    except Tkinter.TclError:
        print "Using default library and include directories for Tcl and 
Tk because a"
        print "Tk window failed to open.  You may need to define DISPLAY 
for Tk to work"
        print "so that setup can determine where your libraries are 
located."

The 'import gtk' at line 149 in setup.py also fails if DISPLAY is not set.

Re: [Matplotlib-users] Building on fedora3?

[Fernando P. <Fer...@co...>]

Stephen Walton wrote:
> Happy New Year, Fernando!
> 
> Gee, I can't believe I can answer one of your questions :-)

Well, I'm happy to give you a chance to help :)

> 
>>/usr/include/pygtk-2.0/pygobject.h:140: error: expected `,' or `...' 
>>before "typename"
>>/usr/include/pygtk-2.0/pygobject.h:147: error: expected `,' or `...' 
>>before "typename"
>>error: command 'gcc' failed with exit status 1
> 
> 
> It's a known typo in the referenced two lines in pygobject.h.  Until a 
> patch is released, manually change "typename" to "_typename";  it's just 
> in the function prototype so the name doesn't matter.

Ah, many thanks!  After fixing this, it all worked great, except for one 
confusing little accident I'll mention in case someone else has the same 
problem.

I was getting a 'pygtk present but import failed' message, which I couldn't 
understand.  I modified setup.py to reraise the exception at that point, and 
it turned out to be a RuntimeError('could not open display') exception.  Well, 
it happens that I do a lot of my sysadmin work using screen, so that I can 
reattach to a session from anywhere, or leave long-running compiles going.  By 
default, screen blocks X11 (I need to learn how to fix this), so the gtk 
initialization was failing due to lack of access to my display, even though 
the library is all there.  The fix was to run the bdist_rpm _outside_ of 
screen, but it might be worth changing the setup file so that this error does 
not crash the build.  I'm not sure it should really be necessary to have a 
running X11 for the build, as long as all the necessary headers and libraries 
are present.

Anyway, thanks again (and also to Vineet) for the help.  You saved me a lot of 
frustration.

Regards,

f

RE: [Matplotlib-users] Building on fedora3?

[Vineet J. <vi...@al...>]

I just spent half a day on this. There should be an entry in the release
notes on this. 

I found a reference to the problem here:

http://www.daa.com.au/pipermail/pygtk/2004-October/008826.html

I downloaded the latest version of pygobject.h and everything worked agains.



Vinjvinj


-----Original Message-----
From: mat...@li...
[mailto:mat...@li...] On Behalf Of Fernando
Perez
Sent: Monday, January 03, 2005 8:33 PM
To: mat...@li...
Subject: [Matplotlib-users] Building on fedora3?

Hi all,

I wonder if anyone is using FedoraCore3.  I'd been recently building 
matplotlib RPMs with my Fedora 2 destktop without any troubles (after
patching 
distutils to ignore a multiple RPMs assertion).  I just upgraded my desktop
to 
Fedora 3, and now the build fails with:

root@planck[matplotlib-0.70]# python setup.py build
running build
running build_py
running build_ext
building 'matplotlib.backends._gtkagg' extension
gcc -pthread -fno-strict-aliasing -DNDEBUG -O2 -g -pipe -m32 -march=i386 
-mtune=pentium4 -D_GNU_SOURCE -fPIC -fPIC -I/usr/local/include
-I/usr/include 
-Isrc -Iagg22/include -I. -I/usr/local/include -I/usr/include 
-I/usr/local/include/freetype2 -I/usr/include/freetype2 -Isrc/freetype2 
-Iagg22/include/freetype2 -I./freetype2 -I/usr/local/include/freetype2 
-I/usr/include/freetype2 -I/usr/local/include -I/usr/include 
-I/usr/include/pygtk-2.0 -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include

-I/usr/include/gtk-2.0 -I/usr/lib/gtk-2.0/include -I/usr/X11R6/include 
-I/usr/include/atk-1.0 -I/usr/include/pango-1.0 -I/usr/include/freetype2 
-I/usr/include/freetype2/config -I/usr/include/glib-2.0 
-I/usr/lib/glib-2.0/include -I/usr/include/python2.3 -c src/_gtkagg.cpp -o 
build/temp.linux-i686-2.3/src/_gtkagg.o
In file included from /usr/include/python2.3/Python.h:8,
                  from /usr/include/pygtk-2.0/pygobject.h:5,
                  from src/_gtkagg.cpp:8:
/usr/include/python2.3/pyconfig.h:850:1: warning: "_POSIX_C_SOURCE"
redefined
In file included from /usr/include/string.h:26,
                  from 
/usr/lib/gcc/i386-redhat-linux/3.4.2/../../../../include/c++/3.4.2/cstring:5
1,
                  from src/_gtkagg.cpp:1:
/usr/include/features.h:150:1: warning: this is the location of the previous

definition
In file included from src/_gtkagg.cpp:8:
/usr/include/pygtk-2.0/pygobject.h:140: error: expected `,' or `...' before 
"typename"
/usr/include/pygtk-2.0/pygobject.h:147: error: expected `,' or `...' before 
"typename"
error: command 'gcc' failed with exit status 1


Does anyone have a hint of what may be going on here?  I looked at the 
pygobject.h file, but nothing jumps to my eye as obviously wrong.

Any help would be much appreciated.

Cheers,

f


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Re: [Matplotlib-users] Building on fedora3?

[Stephen W. <ste...@cs...>]

Happy New Year, Fernando!

Gee, I can't believe I can answer one of your questions :-)

> /usr/include/pygtk-2.0/pygobject.h:140: error: expected `,' or `...' 
> before "typename"
> /usr/include/pygtk-2.0/pygobject.h:147: error: expected `,' or `...' 
> before "typename"
> error: command 'gcc' failed with exit status 1

It's a known typo in the referenced two lines in pygobject.h.  Until a 
patch is released, manually change "typename" to "_typename";  it's just 
in the function prototype so the name doesn't matter.

Best of all, on FC3, 'python setup.py bdist_rpm' works great and 
generates a distributable RPM provided one is mindful of the dependency 
on a statically linked, architecture-specific ATLAS library.

Steve Walton

[Matplotlib-users] Building on fedora3?

[Fernando P. <Fer...@co...>]

Hi all,

I wonder if anyone is using FedoraCore3.  I'd been recently building 
matplotlib RPMs with my Fedora 2 destktop without any troubles (after patching 
distutils to ignore a multiple RPMs assertion).  I just upgraded my desktop to 
Fedora 3, and now the build fails with:

root@planck[matplotlib-0.70]# python setup.py build
running build
running build_py
running build_ext
building 'matplotlib.backends._gtkagg' extension
gcc -pthread -fno-strict-aliasing -DNDEBUG -O2 -g -pipe -m32 -march=i386 
-mtune=pentium4 -D_GNU_SOURCE -fPIC -fPIC -I/usr/local/include -I/usr/include 
-Isrc -Iagg22/include -I. -I/usr/local/include -I/usr/include 
-I/usr/local/include/freetype2 -I/usr/include/freetype2 -Isrc/freetype2 
-Iagg22/include/freetype2 -I./freetype2 -I/usr/local/include/freetype2 
-I/usr/include/freetype2 -I/usr/local/include -I/usr/include 
-I/usr/include/pygtk-2.0 -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include 
-I/usr/include/gtk-2.0 -I/usr/lib/gtk-2.0/include -I/usr/X11R6/include 
-I/usr/include/atk-1.0 -I/usr/include/pango-1.0 -I/usr/include/freetype2 
-I/usr/include/freetype2/config -I/usr/include/glib-2.0 
-I/usr/lib/glib-2.0/include -I/usr/include/python2.3 -c src/_gtkagg.cpp -o 
build/temp.linux-i686-2.3/src/_gtkagg.o
In file included from /usr/include/python2.3/Python.h:8,
                  from /usr/include/pygtk-2.0/pygobject.h:5,
                  from src/_gtkagg.cpp:8:
/usr/include/python2.3/pyconfig.h:850:1: warning: "_POSIX_C_SOURCE" redefined
In file included from /usr/include/string.h:26,
                  from 
/usr/lib/gcc/i386-redhat-linux/3.4.2/../../../../include/c++/3.4.2/cstring:51,
                  from src/_gtkagg.cpp:1:
/usr/include/features.h:150:1: warning: this is the location of the previous 
definition
In file included from src/_gtkagg.cpp:8:
/usr/include/pygtk-2.0/pygobject.h:140: error: expected `,' or `...' before 
"typename"
/usr/include/pygtk-2.0/pygobject.h:147: error: expected `,' or `...' before 
"typename"
error: command 'gcc' failed with exit status 1


Does anyone have a hint of what may be going on here?  I looked at the 
pygobject.h file, but nothing jumps to my eye as obviously wrong.

Any help would be much appreciated.

Cheers,

f

[Matplotlib-users] bug in zooming an image with aspect='preserve'

[Stephen W. <ste...@cs...>]

This seems to be related to the bug reported by Eric Emsellem.  If I do 
an imshow of an image with aspect='preserve' and activate the 'zoom to 
rectangle' function, the zoomed portion of the image is offset from the 
portion I outline with the cursor.

Re: [Matplotlib-users] ANN: matplotlib-0.65.1

[Stephen W. <ste...@cs...>]

Stephen Walton wrote:

> second would be a windowed, scrollable view into an image which is 
> larger than the physical display.

Actually, imshow seems almost to do this.  I did

imshow(imdata,interpolation='nearest')

where imdata was a 1024 square image.  Zooming and panning _seems_ to 
show the full resolution image with individual pixels visible at high 
zooms.  Is this right?

Re: [Matplotlib-users] ANN: matplotlib-0.65.1

[Stephen W. <ste...@cs...>]

John Hunter wrote:

>    Stephen> [...] ability to load multiple aligned images and blink between
>    Stephen> them.
>
>With the new keypress event handling in matplotlib-0.70, and the
>cleanup to make sure the visible property is respected, this is pretty
>easy.
>  
>
You're right, thanks for the example code!

>What's the second item on the list :-)
>  
>
Well, since you asked, and Todd originally mentioned a DS9 replacement:  
second would be a windowed, scrollable view into an image which is 
larger than the physical display.  I have 2K square cameras at my 
observatory, and HST ACS images are 4K square;  both are quite a bit 
larger than any display I'm likely to be able to afford in the 
forseeable future.

Third item, and this will be a lot harder, is display and readout of 
FITS WCS information on the screen.

Acronym glossary:
HST--Hubble Space Telescope
ACS--Advanced Camera for Surveys
FITS--Flexible Image Transport System, the default format for 
astronomical images (http://fits.gsfc.nasa.gov)
WCS--World Coordinate System, a standard for embedding information for 
mapping pixel to physical coordinates in the FITS image header

Re: [Matplotlib-users] contour question

[Nadezhda D. <den...@st...>]

It's a bug in the contour function. 

In axes.py, in function 'contour', put the line 

y, x = indices((jmax,imax), 'd')

in a condition, for example:

if x == None and y == None:
    y, x = indices((jmax,imax), 'd')


A permanent fix will go in CVS next week.

Nadia Dencheva

---- Original message ----
>Date: Sat, 01 Jan 2005 08:05:12 -0700
>From: Jeff Whitaker <js...@fa...>  
>Subject: [Matplotlib-users] contour question  
>To: "'matplotlib-users'" <mat...@li...>
>
>Hi all:
>
>I was experimenting with the contour demo and discovered that
the x and 
>y keyword arguments don't behave like I expect them to (i.e.
they don't 
>behave as they do in pcolor).
>
>For example:
>
>from pylab import *
>delta = 0.025
>x = y = arange(-3.0, 3.0, delta)
>X, Y = meshgrid(x, y)
>Z1 = bivariate_normal(X, Y, 1.0, 1.0, 0.0, 0.0)
>Z2 = bivariate_normal(X, Y, 1.5, 0.5, 1, 1)
>#levels, colls = contour(Z2-Z1, x=X,y=Y,levels=6,
>#                       linewidths=arange(.5, 4, .5),
>#                       colors=('r', 'green', 'blue', (1,1,0), 
>'#afeeee', 0.5),
>#                     origin='lower')
>pcolor(X,Y,Z2-Z1,shading='flat')
>show()
>
>plots the data with the x and y axes going from -3 to +3. 
Uncommenting 
>the contour call, the axes then are the same as the
dimensions of the Z 
>array, regardless of whether the x=X, y=Y keyword args are
given.  In 
>other words, contour seems to ignore the x,y keywords.  Am I
missing 
>something?
>
>-Jeff
>
>-- 
>Jeffrey S. Whitaker         Phone : (30the3)497-6313
>NOAA/OAR/CDC  R/CDC1        FAX   : (303)497-6449
>325 Broadway                Web   : http://www.cdc.noaa.gov/~jsw
>Boulder, CO, USA 80305-3328 Office: Skaggs Research Cntr 1D-124
>
>
>
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>Get a FREE limited edition SourceForge.net t-shirt from
ThinkGeek.
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[Matplotlib-users] ANN: Copacabana

[John H. <jdh...@ac...>]

I'm taking off this afternoon for a vacation in sunny Brazil!  So I
may not be as responsive around here as I sometimes am, though I will
be occasionally checking my email.

Hold down the fort, and I'll think warmly of all of you who may be
stuck in the northern hemisphere :-)

JDH

[Matplotlib-users] contour question

[Jeff W. <js...@fa...>]

Hi all:

I was experimenting with the contour demo and discovered that the x and 
y keyword arguments don't behave like I expect them to (i.e. they don't 
behave as they do in pcolor).

For example:

from pylab import *
delta = 0.025
x = y = arange(-3.0, 3.0, delta)
X, Y = meshgrid(x, y)
Z1 = bivariate_normal(X, Y, 1.0, 1.0, 0.0, 0.0)
Z2 = bivariate_normal(X, Y, 1.5, 0.5, 1, 1)
#levels, colls = contour(Z2-Z1, x=X,y=Y,levels=6,
#                       linewidths=arange(.5, 4, .5),
#                       colors=('r', 'green', 'blue', (1,1,0), 
'#afeeee', 0.5),
#                     origin='lower')
pcolor(X,Y,Z2-Z1,shading='flat')
show()

plots the data with the x and y axes going from -3 to +3.  Uncommenting 
the contour call, the axes then are the same as the dimensions of the Z 
array, regardless of whether the x=X, y=Y keyword args are given.  In 
other words, contour seems to ignore the x,y keywords.  Am I missing 
something?

-Jeff

-- 
Jeffrey S. Whitaker         Phone : (30the3)497-6313
NOAA/OAR/CDC  R/CDC1        FAX   : (303)497-6449
325 Broadway                Web   : http://www.cdc.noaa.gov/~jsw
Boulder, CO, USA 80305-3328 Office: Skaggs Research Cntr 1D-124

Re: [Matplotlib-users] IPython & subplot

[John H. <jdh...@ac...>]

>>>>> "Randy" == Randy Heiland <he...@in...> writes:

    Randy> I'm just playing with matplotlib inside IPython for my
    Randy> first time and want to do the equivalent of:

    Randy> In [1]: subplot(211) In [2]: plot([1,2,3]) In [3]: show()
    -> displays as expected, in the upper half

Use ipython in the pylab mode -- it will detect your backend and do
the right thing if threading is required, and will set the matplotlib
interactive state to be True.

 > ipython --pylab

It will also set you to be in interactive mode, and no use of "show"
is required -- see http://matplotlib.sf.net/interactive.html and
http://matplotlib.sf.net/faq.html#SHOW.  

    Randy> Now I want to interactively display a 2nd plot in the
    Randy> bottom, but when I do: In [4]: subplot(212)

    Randy> I get a new, single empty plot displayed in the lower half.
    Randy> Is there some 'hold' cmd I'm missing to do this?

In matplotlibrc -- http://matplotlib.sf.net/.matplotlibrc -- there is
an axes.hold parameter.  matplotlib ships with axes.hold : True by
default, so this should be your setting unless you changed it in a
past life.  It may be that the strangeness you are seeing vis-a-vis
subplot(212) stems from not using interactive mode properly in
conjunction with unsupported use of show, which should not be used in
interactive mode as explained in the FAQ.

You can query the current hold state with "ishold" and set it with "hold".
Notice in the following pylab interactive session I don't need to
import pylab as ipython does it for me; just make sure you're using a
recent version of ipython and matplotlib.

John-Hunters-Computer:~> ipython --pylab
Python 2.3 (#1, Sep 13 2003, 00:49:11) 
Type "copyright", "credits" or "license" for more information.

IPython 0.6.6 -- An enhanced Interactive Python.
?       -> Introduction to IPython's features.
%magic  -> Information about IPython's 'magic' % functions.
help    -> Python's own help system.
object? -> Details about 'object'. ?object also works, ?? prints more.

  Welcome to pylab, a matplotlib-based Python environment
    help(matplotlib) -> generic matplotlib information
    help(pylab)     -> matlab-compatible commands from matplotlib
    help(plotting)   -> plotting commands

In [1]: ishold()
Out[1]: True

In [2]: hold(False)

In [3]: ishold()
Out[3]: False

In [4]: 

[Matplotlib-users] IPython & subplot

[Randy H. <he...@in...>]

I'm just playing with matplotlib inside IPython for my first time and want
to do the equivalent of:

In [1]: subplot(211)
In [2]: plot([1,2,3])
In [3]: show()
-> displays as expected, in the upper half
Now I want to interactively display a 2nd plot in the bottom, but when I do:
In [4]: subplot(212)

I get a new, single empty plot displayed in the lower half.
Is there some 'hold' cmd I'm missing to do this?

--Randy

[Matplotlib-users] map plotting module

[Jeff W. <js...@fa...>]

Hi:

The first version of a map plotting module is available at 
http://www.cdc.noaa.gov/people/jeffrey.s.whitaker/python/basemap/

(Source code
http://www.cdc.noaa.gov/people/jeffrey.s.whitaker/python/basemap/basemap-20041229.tar.gz)

It's not nearly as fully featured as the the matlab mapping toolbox, nor does it have the same API - but it does provide some useful functions for plotting images and contour plots on mercator, lat/lon, lambert conformal and stereographic projections.  Plotting coastlines, countries boundaries and state boundaries in the Americas is supported.  Filling continents is supported, but filling ocean areas is not (yet).  There are also functions to plot selected parallels and meridians, as well as an interpolation function to regrid regularly spaced lat/lon data to a native map projection grid.  

In addition to numarray and matplotlib, the module requires proj (from http://proj.maptools.org).

Hope someone finds it useful - comments and suggestions are welcome.

-Jeff

-- 
Jeffrey S. Whitaker         Phone : (303)497-6313
NOAA/OAR/CDC  R/CDC1        FAX   : (303)497-6449
325 Broadway                Web   : http://www.cdc.noaa.gov/~jsw
Boulder, CO, USA 80305-3328 Office: Skaggs Research Cntr 1D-124

Re: [Matplotlib-users] ANN: matplotlib-0.65.1

[John H. <jdh...@ac...>]

    Stephen> Sounds like an interesting project.  The first item I'd
    Stephen> have on a list of desired features is, surprise, the
    Stephen> ability to load multiple aligned images and blink between
    Stephen> them.

With the new keypress event handling in matplotlib-0.70, and the
cleanup to make sure the visible property is respected, this is pretty
easy.  The example below is more complicated than you need for the
usual case, since it handles images of different pixel dimensions that
occupy the same physical dimensions, but it gives you the idea (btw,
this is now examples/toggle_images.py, which contains a bit more
information in the header)

What's the second item on the list :-)

JDH

from pylab import *

# two images x1 is initially visible, x2 is not
x1 = rand(100, 100)
x2 = rand(150, 175)

# arbitrary extent - both images must have same extent if you want
# them to be resampled into the same axes space
extent = (0,1,0,1) 
im1 = imshow(x1, extent=extent)
im2 = imshow(x2, extent=extent, hold=True)
im2.set_visible(False)

def toggle_images(event):
    'toggle the visible state of the two images'
    if event.key != 't': return
    b1 = im1.get_visible()
    b2 = im2.get_visible()
    im1.set_visible(not b1)
    im2.set_visible(not b2)
    draw()

connect('key_press_event', toggle_images)
#savefig('toggle_images')
show()

[Matplotlib-users] ANN: matplotlib-0.70

[John H. <jdh...@ac...>]

This is (hopefully) a final rollup of what is (should be) a fairly
stable tree.  Mainly I wanted to send a release notification out to
the larger python community (scipy/numpy/python-list) since I haven't
done that since 0.60 (July 2004).  

For the major releases, I tend to try and shy away from new features
preferring a stable src.  But for you hardened, grizzled matplotlib
veterans, there are a few enticements nonetheless

 - pie charts and new example/pie_demo.py.  See
   http://matplotlib.sf.net/screenshots.html#pie_demo

 - support for object picking - see examples/picker_demo.py.  As
   people test this out and we settle on an interface, this will
   probably become part of the core, as will other keypress
   functionality for navigation, grid toogle, zoom toggle etc.

 - Fixed coords notification in wx toolbar 

 - key press and release event supported across backends -- see
   examples/keypress_demo.py

 - added Shadow patch class to provide a shadow effect for polygons,
   legends, pie charts -
   http://matplotlib.sf.net/screenshots.html#legend_demo

 - new examples/text_rotation.py demonstrates how text rotations and
   alignment work in matplotlib.  

Bug fixes

  - Fixed PS mathtext bug where color was not set

  - Fixed an agg text rotation alignment bug, fixed some text kwarg
    processing bugs

  - Refactored event handling - multiple connects and disconnects now
    work across backends.  See examples/coords_demo.py, especially
    with test_disconnect

  - Fixed a tkagg interactive bug that caused segfaults in some
    conditions.

As usual, downloads at http://sourceforge.net/projects/matplotlib

JDH

Re: [Matplotlib-users] how show values *decreasing* up the y-axis like in a pcolor plot?

[John H. <jdh...@ac...>]

>>>>> "seberino" == seberino  <seb...@sp...> writes:

    seberino> Normally x-axis (horizontal) values increase to right
    seberino> and y-axis (vertical) values increase up the page.

    seberino> Is it easy/possible to reverse this for the y-axis??
    seberino> (So that y-values **decrease** up the page for some
    seberino> range?)

  ylim(ymax, ymin)

OR

  xlim(xmax, xmin)

See, for example, http://matplotlib.sf.net/examples/invert_axes.py

Re: [Matplotlib-users] nonuniform meshes

[John H. <jdh...@ac...>]

>>>>> "Randy" == Randy Heiland <he...@in...> writes:

    Randy> Can matplotlib do image plots of a nonuniform mesh?  from
    Randy> matplotlib.matlab import *

    Randy> x=array([0.,0.5,0.51,4.])  y=array([0.,1.])  X,Y =
    Randy> meshgrid(x,y) Z=array([[0,1,1,2],[0,1,1,2]]) im =
    Randy> imshow(Z,cmap=cm.jet) show()

Yes, but note that the pcolor has numrows-1 rows and numcols-1 cols
since the endpoints must be specified in your X,Y arrays

    x = array([0.,0.5,0.6,4.])
    y = array([0.,1.,4])
    X,Y = meshgrid(x,y)
    Z = array([[0,1,2,2],[0,1,1,2],[2,0,1,2]])
    pcolor(X, Y, Z, cmap=cm.jet)

JDH

[Matplotlib-users] nonuniform meshes

[Randy H. <he...@in...>]

Can matplotlib do image plots of a nonuniform mesh?

from matplotlib.matlab import *

x=array([0.,0.5,0.51,4.])
y=array([0.,1.])
X,Y = meshgrid(x,y)
Z=array([[0,1,1,2],[0,1,1,2]])
im = imshow(Z,cmap=cm.jet)
show()

thanks, Randy

[Matplotlib-users] how show values *decreasing* up the y-axis like in a pcolor plot?

[<seb...@sp...>]

Normally x-axis (horizontal) values increase to right
and y-axis (vertical) values increase up the page.

Is it easy/possible to reverse this for the y-axis??
(So that y-values **decrease** up the page for some range?)

Chris
--
_______________________________________

Christian Seberino, Ph.D.
SPAWAR Systems Center San Diego
Code 2872
49258 Mills Street, Room 158
San Diego, CA 92152-5385
U.S.A.

Phone: (619) 553-9973
Fax  : (619) 553-6521
Email: seb...@sp...
_______________________________________

Re: [Matplotlib-users] pcolor plot question about empty horizontal strip at top

[John H. <jdh...@ac...>]

>>>>> "seberino" == seberino  <seb...@sp...> writes:

    seberino> It seems if your grid has 20 rows ( different y values)
    seberino> of points that you won't get 20 colored horizontal
    seberino> strips but rather *19*.  This is because we must lose
    seberino> one row to specify the top and/or bottom EDGE of the
    seberino> plot.... so XX rows means (XX-1) rows of colored
    seberino> squares.

yep that's right, a frequent source of confusion.  

    seberino> Please tell me if this is right but more importantly,
    seberino> how to most wisely remove the white horizontal strip
    seberino> from this pcolor plot.

Well it would help if you posted your code, but my guess is that you
need to set your axis limits to equal your ymin/ymax of the pcolor.

Perhaps this example will give you a hint

   >>> pcolor(rand(10,7))  # no white strip...
   >>> ylim(0,11)          # a white strip because the ylim is wrong

In essence, the axis autoscaler will round up, eg 4990 to 5000, to
make nice integer ticks.  With pcolors and images, you often don't
want this, so use the axis, xlim, and/or ylim commands to set the
limits properly.

Eg

  ymin = min(ravel(Y))
  ymax = max(ravel(Y))
  ylim(ymin, ymax)

Also, if your x and y grids are equally spaced, you'll get much better
performance for large arrays, as well as more interpolation options,
if you use imshow with the extent kwarg to set the extent of your
image data.

JDH