matplotlib-devel Mailing List for matplotlib

On Aug 30, 2005, at 10:45 AM, Arnd Baecker wrote:
> I would have thought so as well. However I get:
<snip>
> A search for wxPython.h on
> http://www.debian.org/distrib/packages#search_packages
> gives no hits.

Sorry, due to a lack of coffee this morning I misread "wxPython.h" as 
"wxWidgets.h" or something daft, yielding the kneejerk "install the 
-dev package" response.

I wasn't aware of this situation, but it has the potential to be a big 
problem for me at work, where we primarily run Debian.  I have emailed 
Ron Lee, the wxgtk2.4 package maintainer, about the situation.  We'll 
see what he has to say on the matter.

> I agree. I wonder if anything improved with wx2.6? (for our 
> PlottingCanvas
> we even dared to keep drawing DCs around, and it works without 
> problems...)

What PlottingCanvas is this?  I'd be interested in seeing what 
optimizations you guys performed, if the source is available.

>> However, I think there are a couple pieces of lower-handing fruit, 
>> like not
>> making an extra source copy when blitting (_wxagg.cpp:159-190), that 
>> will
>> offer speedups.
>
> That would be cool (I have to admit, that I am not too worried when  
> FPS>100
> on my machine. However, we are currently investigating to use 
> matplotlib for
> a computational physics course (which will be next summer) and many of 
> the
> students have *much* slower machines. So we need maximum speed but 
> with a
> minimum of coding hassle (around 30% of the students have never 
> programmed
> before ...).

Just leveling the playing field between WXAgg and GtkAgg is exciting 
for me, because that means that future efforts at general optimization 
will net a bigger speed improvement for WXAgg.

I'd imagine the plotting speed will be good enough for something along 
the lines of interactive plotting with iPython or visualizing results 
with pylab.  Speaking as a recent survivor of a computational physics 
class, I expect you to see a huge benefit from using Python as the 
language and matplotlib as the visualization, especially if you have 
students who have never programmed before.

Ken

Ken, all,

I'd tried this patch out on Mac OS X, with standard Mac-based python
and wxPython 2.6. I had to explicitly set the environmental variable
WX_CONFIG, but after that it built fine and runs fine.

For my scripts on a slow G4 Powerbook, I see a small improvement in
speed compared with mpl 0.81.  I'll be eager to try this on Windows.

Thanks Ken,

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

>>>>> "Arnd" == Arnd Baecker <arn...@we...> writes:

    >> It does have wxPython.h, it's just not in the libwxgtk2.4
    >> package.  You'll need to install the libwxgtk2.4-dev package as
    >> well to get the headers.

    Arnd> I would have thought so as well. However I get:
    ....
    Arnd> A search for wxPython.h on
    Arnd> http://www.debian.org/distrib/packages#search_packages gives
    Arnd> no hits.

I found this too -- it may be rightly considered a bug in the dev
package.  I checked out the src package and then copied over the
headers.  The following worked for me


   apt-get source libwxgtk2.5.3
   sudo cp -a wxwidgets2.5-2.5.3.2ubuntu4/include/wx-2.5/wx/wxPython /usr/include/wx-2.5/wx/

JDH

Hi,

On Tue, 30 Aug 2005, Ken McIvor wrote:
> On Aug 30, 2005, at 9:31 AM, Arnd Baecker wrote:
[...]

> > a) debian problem:
> >    Very interestingly debian stable (sarge)
> >    does not have wxPython.h
>
> It does have wxPython.h, it's just not in the libwxgtk2.4 package.
> You'll need to install the libwxgtk2.4-dev package as well to get the
> headers.

I would have thought so as well. However I get:

dpkg -L libwxgtk2.4-dev
/.
/usr
/usr/bin
/usr/bin/wxgtk-2.4-config
/usr/lib
/usr/lib/wx
/usr/lib/wx/include
/usr/lib/wx/include/univ
/usr/lib/wx/include/gtk-2.4
/usr/lib/wx/include/gtk-2.4/wx
/usr/lib/wx/include/gtk-2.4/wx/setup.h
/usr/lib/libwx_gtk-2.4.a
/usr/lib/libwx_gtk_gl-2.4.a
/usr/share
/usr/share/doc
/usr/share/doc/libwxgtk2.4-dev
/usr/share/doc/libwxgtk2.4-dev/copyright
/usr/share/doc/libwxgtk2.4-dev/changelog.gz
/usr/share/man
/usr/share/man/man1
/usr/lib/libwx_gtk-2.4.so
/usr/lib/libwx_gtk_gl-2.4.so
/usr/share/man/man1/wxgtk-2.4-config.1.gz

A search for wxPython.h on
http://www.debian.org/distrib/packages#search_packages
gives no hits.


> >   GTKAgg               FPS: 131.897223221
> >   TkAgg                FPS:  65.5153012595
> >   WXAgg                FPS: 100.55
> >      (200 frames: 1.99 seconds,   200 blits:  0.95 seconds)
> >      (FPS: 100.55                 BPS: 211.00)
> >   WXAgg --no-accel     FPS: 53.21
> >      (200 frames: 3.76 seconds,   200 blits:  2.55 seconds
> >      (FPS: 53.21                  BPS: 78.40)
> >
> >
> > I am running debian sarge, on a PIV, 2.8 GHz and an nVdia Quadro4 NVS
> > graphics card (@1600x1200).
> > So WXAgg is almost on par with GTGAgg - great!!
>
> That's very exciting news.  I hadn't had a chance to test and profile
> the accelerator under Debian, nor had I bothered profiling it against
> GtkAgg and TkAgg under OSX.  I should probably get those backends up
> and running (darn macs) and do so.
>
> > Ken, in _wxagg.cpp you mention that you planned to write a
> > agg_to_wx_bitmap()
> > which draws directly to a bitmap, but that this might not speed up
> > things
> > much because of: AGG->wx.Image->wx.Bitmap before you can blit using a
> > MemoryDC.
>
> Yes, I am concerned that re-implementing that part of the blit into C++
> won't speed things up enough.  I can understand doing the whole
> Image/Bitmap thing for portability (especially when wxWindows got
> started in 1992), but it's rather obnoxious when all it does is make
> extra copies of RGB data.

I agree. I wonder if anything improved with wx2.6?
(for our PlottingCanvas we even dared to keep
drawing DCs around, and it works without problems...)

> However, I think there are a couple pieces
> of lower-handing fruit, like not making an extra source copy when
> blitting (_wxagg.cpp:159-190), that will offer speedups.

That would be cool
(I have to admit, that I am not too worried when  FPS>100
on my machine. However, we are currently investigating
to use matplotlib for a computational physics course
(which will be next summer) and many of the students
have *much* slower machines. So we need maximum speed
but with a minimum of coding hassle (around 30% of the students
have never programmed before ...).

> Unfortunately, they'd be portable across Agg backends, so GtkAgg would
> get faster too.  ;-)

I would not mind too much ;-).

> > Maybe you can contact Chris Barker if he has an idea on this (or are
> > there any
> > solutions available in the context of wxart2d or chaco? - quick
> > googling did not
> > reveal anything ...)
>
> I'll do so, if he doesn't see this part of the message than chime in.
> I have come across some old wxWindows mailing list exchanges indicating
> that there's no way to avoid the Image->Bitmap conversion as a
> requirement for drawing RGB images, so I'm not planning to loose too
> much sleep over it.  I hadn't heard about wxart2d before, but will look
> into it to see how their agg canvas is implemented.  I'll see if I can
> find the chaco repository and do the same there.
>
> Thanks for sharing your anim.py profiling results.  It's heartening to
> see WXAgg's full-redraw speed being limited by the rest of matplotlib,
> rather than the backend.

Indeed this is good news!! Many thanks,

Arnd

On Aug 30, 2005, at 9:31 AM, Arnd Baecker wrote:
> Many thanks for the update of the patch.
> It turned out that I could not apply it to this mornings CVS checkout
> because John's time machine was already active  and he has put your
> patch into CVS ;-)

Really?  Yay for me!  ;-)

> During installation I encountered two glitches:
>
> a) debian problem:
>    Very interestingly debian stable (sarge)
>    does not have wxPython.h

It does have wxPython.h, it's just not in the libwxgtk2.4 package.  
You'll need to install the libwxgtk2.4-dev package as well to get the 
headers.

>   GTKAgg               FPS: 131.897223221
>   TkAgg                FPS:  65.5153012595
>   WXAgg                FPS: 100.55
>      (200 frames: 1.99 seconds,   200 blits:  0.95 seconds)
>      (FPS: 100.55                 BPS: 211.00)
>   WXAgg --no-accel     FPS: 53.21
>      (200 frames: 3.76 seconds,   200 blits:  2.55 seconds
>      (FPS: 53.21                  BPS: 78.40)
>
>
> I am running debian sarge, on a PIV, 2.8 GHz and an nVdia Quadro4 NVS
> graphics card (@1600x1200).
> So WXAgg is almost on par with GTGAgg - great!!

That's very exciting news.  I hadn't had a chance to test and profile 
the accelerator under Debian, nor had I bothered profiling it against 
GtkAgg and TkAgg under OSX.  I should probably get those backends up 
and running (darn macs) and do so.

> Ken, in _wxagg.cpp you mention that you planned to write a 
> agg_to_wx_bitmap()
> which draws directly to a bitmap, but that this might not speed up 
> things
> much because of: AGG->wx.Image->wx.Bitmap before you can blit using a 
> MemoryDC.

Yes, I am concerned that re-implementing that part of the blit into C++ 
won't speed things up enough.  I can understand doing the whole 
Image/Bitmap thing for portability (especially when wxWindows got 
started in 1992), but it's rather obnoxious when all it does is make 
extra copies of RGB data.  However, I think there are a couple pieces 
of lower-handing fruit, like not making an extra source copy when 
blitting (_wxagg.cpp:159-190), that will offer speedups.  
Unfortunately, they'd be portable across Agg backends, so GtkAgg would 
get faster too.  ;-)

> Maybe you can contact Chris Barker if he has an idea on this (or are 
> there any
> solutions available in the context of wxart2d or chaco? - quick 
> googling did not
> reveal anything ...)

I'll do so, if he doesn't see this part of the message than chime in.  
I have come across some old wxWindows mailing list exchanges indicating 
that there's no way to avoid the Image->Bitmap conversion as a 
requirement for drawing RGB images, so I'm not planning to loose too 
much sleep over it.  I hadn't heard about wxart2d before, but will look 
into it to see how their agg canvas is implemented.  I'll see if I can 
find the chaco repository and do the same there.

Thanks for sharing your anim.py profiling results.  It's heartening to 
see WXAgg's full-redraw speed being limited by the rest of matplotlib, 
rather than the backend.

Ken

Hi Ken,

On Mon, 29 Aug 2005, Ken McIvor wrote:

[...]

> I will resubmit the wx-anim.tar.gz patch to sourceforge with this
> correction.

Many thanks for the update of the patch.
It turned out that I could not apply it to this mornings CVS checkout
because John's time machine was already active  and he has put your
patch into CVS ;-)

During installation I encountered two glitches:

a) debian problem:
   Very interestingly debian stable (sarge)
   does not have wxPython.h
   As a work-around I downloaded the corresponding source from debian
    wget
http://ftp.debian.org/debian/pool/main/w/wxwindows2.4/wxwindows2.4_2.4.3.1.tar.gz
   and copied all header files wxwindows2.4-2.4.3.1/wxPython/src/*.h
   to a (newly created) /usr/include/wx/wxPython.

   Then the installation went fine.

b) CVS problem:
   Calling python animation_blit_wx.py from the examples directory
   gives the error

  lib/python2.3/site-packages/matplotlib/__init__.py:788: UserWarning:
could not find rc file; returning defaults
    warnings.warn(message)
  Traceback (most recent call last):
    File "animation_blit_wx.py", line 10, in ?
      import pylab as p
    File "/scratch/abaecker/SOFT//lib/python2.3/site-packages/pylab.py",
line 1, in ?
      from matplotlib.pylab import *
    File
"/scratch/abaecker/SOFT//lib/python2.3/site-packages/matplotlib/pylab.py",
line 194, in ?
      import cm
    File
"/scratch/abaecker/SOFT//lib/python2.3/site-packages/matplotlib/cm.py",
line 372, in ?
      atad['Blues']=_Blues_data
  NameError: name '_Blues_data' is not defined


  Commenting out the corresponding block in matplotlib/cm.py
  everything works fine again
  (John: I think this is a leftover from rev. 1.19 for cm.py "removed
extra cmaps until license is resolved")

OK, now to the new WXAgg (and animation in general):


Running:
  python animation_blit.py
  python animation_blit_tk.py
  python animation_blit_wx.py
  python animation_blit_wx.py --no-accel

gives:

  GTKAgg               FPS: 131.897223221
  TkAgg                FPS:  65.5153012595
  WXAgg                FPS: 100.55
     (200 frames: 1.99 seconds,   200 blits:  0.95 seconds)
     (FPS: 100.55                 BPS: 211.00)
  WXAgg --no-accel     FPS: 53.21
     (200 frames: 3.76 seconds,   200 blits:  2.55 seconds
     (FPS: 53.21                  BPS: 78.40)


I am running debian sarge, on a PIV, 2.8 GHz and an nVdia Quadro4 NVS
graphics card (@1600x1200).
So WXAgg is almost on par with GTGAgg - great!!

Ken, in _wxagg.cpp you mention that
you planned to write a agg_to_wx_bitmap() which
draws directly to a bitmap, but that
this might not speed up things much because
of: AGG->wx.Image->wx.Bitmap before you can blit using a MemoryDC.
Maybe you can contact Chris Barker if he has an idea on this
(or are there any solutions available in the context of wxart2d or
chaco? - quick googling did not reveal anything ...)

Anyway, the speed provided by the animate option
is a fantastic improvement - many thanks John and Ken!!

Just for comparison:

for backend in `echo "Tk TkAgg GTK GTKAgg WX WXAgg"`
do
   echo $backend

   python anim.py -d${backend}
done

Tk     FPS: 35.5331434162
TkAgg  FPS: 20.3487964649
GTK    FPS: 35.528699289
GTKAgg FPS: 26.9074415174
WX     FPS: 13.7550465745
WXAgg  FPS: 26.0163513384

Many thanks,

Arnd