matplotlib-users Mailing List for matplotlib (Page 9)

I am trying out quiver using IPython (which I am new to so my apologies if=
=20
this is actually a IPython question) and matplotlib .80 and the latest=20
numeric. The code I try and the subsequent error:

In [1]: x=3Dones([5,5])

In [2]: quiver(x,x)
---------------------------------------------------------------------------
exceptions.TypeError Traceback (most recent call last)

C:\Documents and Settings\root\Desktop\<console>

C:\Python24\Lib\site-packages\matplotlib\pylab.py in quiver(*args, **kwargs=
)
2137 hold(h)
2138 try:
-> 2139 ret =3D gca().quiver(*args, **kwargs)
2140 draw_if_interactive()
2141 except:

C:\Python24\Lib\site-packages\matplotlib\axes.py in quiver(self, U, V,=20
*args, **kwargs)
852 if do_scale:
853 Nmax =3D maximum.reduce(maximum.reduce(N))
--> 854 U *=3D (S/Nmax)
855 V *=3D (S/Nmax)
856 N /=3D Nmax

TypeError: return array has incorrect type


What could be the issue? Thanks for the help.
-Chris

>>>>> "Ryan" == Ryan Krauss <rya...@co...> writes:

    Ryan> I am having a slight problem with my install on FC3 Linux
    Ryan> running KDE.  When I am developing scripts, I like to
    Ryan> generate a lot of plots along the way and want them to
    Ryan> refresh every time I run the script.  When I run the
    Ryan> following code with the TkAgg backend it works o.k., but
    Ryan> with the GTKAgg backend, only the second plot updates:


See examples/dynamic_image_gtkagg.py for an example of how to use gtk
to make dynamic plots.  You can also do this by manipulating the
interactive setting as discussed on 
http://matplotlib.sourceforge.net/interactive.html

You may also want to read this FAQ -
http://matplotlib.sourceforge.net/faq.html#SHOW

Hope this helps...
JDH

I just installed matplotlib and I am really excited about it.  I have 
often thought it would be great to have all of the Matlab plotting 
capabilities without having to pay for their software and now I have 
that and Python.  What could be better?

I am having a slight problem with my install on FC3 Linux running KDE.  
When I am developing scripts, I like to generate a lot of plots along 
the way and want them to refresh every time I run the script.  When I 
run the following code with the TkAgg backend it works o.k., but with 
the GTKAgg backend, only the second plot updates:

from pylab import *
#close('all')
figure(1)
cla()
plot(rand(20),rand(20),'go')

figure(2)
cla()
plot(rand(20),rand(20),'ro')

show()

and uncommenting the close('all') line works fine with TkAgg but sort of 
locks things up with GTKAgg.

I will just use TkAgg for now, but was wondering if I can fix this.

Thanks,

Ryan

Thanks for the tip - figlegend works just fine for my application.  I'll 
file an enhancement for tracking purposes...

Ted

At 07:29 AM 5/12/2005, John Hunter wrote:
> >>>>> "Ted" == Ted Drain <ted...@jp...> writes:
>
>     Ted> Has anyone tried to put a legend in a polar plot?  I get an
>     Ted> error whenever I try this.  To reproduce the error, run the
>     Ted> polar plot demo and then do something like:
>
>     Ted> legend( ( "test" ) )
>     Ted> 
> "/group/monte/development/rhe3/tools.0504/lib/python2.4/site-packages/matplotlib/axes.py",
>     Ted> line 1869, in get_handles handles.extend(self.patches)
>     Ted> AttributeError: PolarAxes instance has no attribute 'patches'
>
>
>     Ted> Should I file this as a bug?  Thanks, Ted Ted Drain Jet
>
>Maybe a feature request?  The problem is deeper than simply adding the
>missing patches attr (which holds a list of patches stored by the
>axes).  If you add that (as I just did), you can run legend w/ no
>traceback but no legend either.  I think the problem is that the
>legend by default uses the axes coordinate system to place the
>rectangle in which the legend resides is being placed in axes
>coordinates, and the axes coordinate system for polar axes is not the
>same as for rectangular axes and this is fouling up the legend
>placement.
>
>There is a workaround using figlegend
>
>   >>> lines = polar(range(10))
>   >>> figlegend(lines, ('my label',), 'upper right')
>
>I think it would be nice for polar axes legend to work automagically,
>so you might want to add this as a feature request on the sf site.  I
>already fixed the patch/traceback crash, but now it just fails
>silently (no legend, no error).  I think I'll add an PolarAxes legend
>NotImplementedError which raises an exceptions and suggests figlegend
>for the time being.
>
>I'm sure there are other surprises one will find when trying to use
>some of the Axes parent methods (eg table) in the PolarAxes.  It
>would be nice if these were also indicated with NotImplementedError
>until they are.  We can fill these in as we find them.
>
>JDH

>>>>> "Ted" == Ted Drain <ted...@jp...> writes:

    Ted> Has anyone tried to put a legend in a polar plot?  I get an
    Ted> error whenever I try this.  To reproduce the error, run the
    Ted> polar plot demo and then do something like:

    Ted> legend( ( "test" ) )
    Ted> "/group/monte/development/rhe3/tools.0504/lib/python2.4/site-packages/matplotlib/axes.py",
    Ted> line 1869, in get_handles handles.extend(self.patches)
    Ted> AttributeError: PolarAxes instance has no attribute 'patches'


    Ted> Should I file this as a bug?  Thanks, Ted Ted Drain Jet

Maybe a feature request?  The problem is deeper than simply adding the
missing patches attr (which holds a list of patches stored by the
axes).  If you add that (as I just did), you can run legend w/ no
traceback but no legend either.  I think the problem is that the
legend by default uses the axes coordinate system to place the
rectangle in which the legend resides is being placed in axes
coordinates, and the axes coordinate system for polar axes is not the
same as for rectangular axes and this is fouling up the legend
placement.

There is a workaround using figlegend

  >>> lines = polar(range(10))
  >>> figlegend(lines, ('my label',), 'upper right')

I think it would be nice for polar axes legend to work automagically,
so you might want to add this as a feature request on the sf site.  I
already fixed the patch/traceback crash, but now it just fails
silently (no legend, no error).  I think I'll add an PolarAxes legend
NotImplementedError which raises an exceptions and suggests figlegend
for the time being.

I'm sure there are other surprises one will find when trying to use
some of the Axes parent methods (eg table) in the PolarAxes.  It
would be nice if these were also indicated with NotImplementedError
until they are.  We can fill these in as we find them.

JDH

Hi John,
here is the plotyy help info.
Cory.

 >> help plotyy

  PLOTYY Graphs with y tick labels on the left and right.
     PLOTYY(X1,Y1,X2,Y2) plots Y1 versus X1 with y-axis labeling
     on the left and plots Y2 versus X2 with y-axis labeling on
     the right.

     PLOTYY(X1,Y1,X2,Y2,FUN) uses the plotting function FUN
     instead of PLOT to produce each plot.  FUN should be a
     function handle to a plotting function, e.g. @plot, @semilogx,
     @semilogy, @loglog ,@stem, etc. that accepts the syntax H = FUN(X,Y).

     PLOTYY(X1,Y1,X2,Y2,FUN1,FUN2) uses FUN1(X1,Y1) to plot the data for
     the left axes and FUN2(X1,Y1) to plot the data for the right axes.

     [AX,H1,H2] = PLOTYY(...) returns the handles of the two axes created in
     AX and the handles of the graphics objects from each plot in H1
     and H2. AX(1) is the left axes and AX(2) is the right axes.

     See also PLOT, @.

 >>

John Hunter wrote:
>>>>>>"Cory" == Cory Davis <cd...@st...> writes:
> 
> 
>     Cory> Hi all, I have now figured out how to do this. It goes
>     Cory> something like...
> 
> That's the basic idea -- matplotlib has some helper functions to make
> this easier -- see examples/shared_axis_demo.py
> 
> What is the signature of plotyy -- I wasn't aware of this function..
> 
> JDH
> 
> 
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-- 
---------------------------------------------------
Cory Davis
Institute for Atmospheric and Environmental Science
Room 307, Crew Building, Kings Buildings,
University of Edinburgh. Edinburgh EH9 3JN
phone: +44 131 6505092
www: http://www.geos.ed.ac.uk/contacts/homes/cdavis

What's the best way to control the radial scale in a polar plot?  For 
example, if I have data like this:

theta = [ 1, 2, 3, 4, 5 ]
rad = [ 10, 20, 30, 40, 50 ]
polar( theta, rad )

How do I make the radial scale go from 0 to 80?  I tried messing with the 
ylim doing something like this:

gca().set_ylim( ( 80*sqrt(2), 80*sqrt(2) ) )

All that seems to do is to scale the whole plot without changing the axis 
bounds.  If I try to set the grid like this:

grids = [ 0, 20, 40, 60, 80 ]
lbls = [ "0", "20", "40", "60", "80" ]
gca().set_rgrids( grid, lbls, frac=1.05 )

The grid lines draw correctly but the background of the plot doesn't change 
to fit the new grid lines.

Thanks,
Ted
Ted Drain     Jet Propulsion Laboratory   ted...@jp...    

Has anyone tried to put a legend in a polar plot?  I get an error whenever 
I try this.  To reproduce the error, run the polar plot demo and then do 
something like:

legend( ( "test" ) )

   File 
"/group/monte/development/rhe3/tools.0504/lib/python2.4/site-packages/matplotlib/pylab.py", 
line 2173, in legend
     ret =  gca().legend(*args, **kwargs)
   File 
"/group/monte/development/rhe3/tools.0504/lib/python2.4/site-packages/matplotlib/axes.py", 
line 1881, in legend
     handles = [h for h, label in zip(get_handles(), labels)]
   File 
"/group/monte/development/rhe3/tools.0504/lib/python2.4/site-packages/matplotlib/axes.py", 
line 1869, in get_handles
     handles.extend(self.patches)
AttributeError: PolarAxes instance has no attribute 'patches'


Should I file this as a bug?
Thanks,
Ted
Ted Drain     Jet Propulsion Laboratory   ted...@jp...    

>>>>> "Cory" == Cory Davis <cd...@st...> writes:

    Cory> Hi all, I have now figured out how to do this. It goes
    Cory> something like...

That's the basic idea -- matplotlib has some helper functions to make
this easier -- see examples/shared_axis_demo.py

What is the signature of plotyy -- I wasn't aware of this function..

JDH

Hi all,
I have now figured out how to do this. It goes something like...

x=arange(10)
y1=sin(x)
y2=10*cos(x)

rect=[0.1,0.1,0.8,0.8]
a1=axes(rect)
a1.yaxis.tick_left()
plot(x,y1)
ylabel('axis 1')
xlabel('x')

a2=axes(rect,frameon=False)
a2.yaxis.tick_right()
plot(x,y2)
a2.yaxis.set_label_position('right')
ylabel('axis 2')
a2.set_xticks([])

Cheers,
Cory.



Cory Davis wrote:
> Hi All,
> I am wanting to make a plot with a secondary y axis, just like the 
> matlab function plotyy does. Does anyone have any tips on how to do this 
> with matplotlib?
> 
> Cheers,
> Cory.
> 
> 

Robert Kern wrote:
> /usr/bin = Apple
> /usr/local/bin = Anybody else

For completeness' sake, that's the same rule for EVERY *nix (replacing 
"Apple" with whatever OS vendor your using)

-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...

Fernando Perez wrote:
> Robert Kern wrote:
> 
>> Fernando Perez wrote:
>>
>>> Matt Newville wrote:
>>
>>>> Maybe you want to make Mac installs put ipython in /usr/bin
>>
>> /usr/local/bin, please.
> 
> Well, the point is that I don't want to make it go _anywhere_ in 
> particular. I want to let distutils do what it's supposed to do, so that 
> relocation commands (--home, --prefix) work correctly, for example, or 
> that installs with non-standard pythons also work as they should.  Which 
> is why I'm resisting hard-coding _any_ paths in there, unless I can be 
> convinced that the solution is a clean one across the board, addressing 
> all these issues.

Yes, that was more advice directed to Matt and anyone else actually 
installing on OS X than it was to you.

/usr/bin = Apple
/usr/local/bin = Anybody else

-- 
Robert Kern
rk...@uc...

"In the fields of hell where the grass grows high
  Are the graves of dreams allowed to die."
   -- Richard Harter

Robert Kern wrote:
> Fernando Perez wrote:
> 
>>Matt Newville wrote:
> 
> 
>>>Maybe you want to make Mac installs put ipython in /usr/bin
> 
> 
> /usr/local/bin, please.

Well, the point is that I don't want to make it go _anywhere_ in particular. 
I want to let distutils do what it's supposed to do, so that relocation 
commands (--home, --prefix) work correctly, for example, or that installs with 
non-standard pythons also work as they should.  Which is why I'm resisting 
hard-coding _any_ paths in there, unless I can be convinced that the solution 
is a clean one across the board, addressing all these issues.

cheers,

f

Fernando Perez wrote:
> Matt Newville wrote:

>> Maybe you want to make Mac installs put ipython in /usr/bin

/usr/local/bin, please.

>> and
>> point to pythonw (which is admittedly just a bash wrapper around
>> /System/Library/..../Python.app/Contents/MacOS/Python)??
> 
> Mmh, the problem is that I don't know how to achieve this in a clean, 
> distutils-based way.  I can't go changing the shebang line by hand, 
> since I don't know where things will end up, and as far as I know there 
> is no way to force this kind of behavior onto distutils. 

FWIW, with the semi-official 2.4.1 framework build, I always get an 
appropriate

#!/usr/bin/env /usr/local/bin/pythonw2.4

-- 
Robert Kern
rk...@uc...

"In the fields of hell where the grass grows high
  Are the graves of dreams allowed to die."
   -- Richard Harter

Hi All,
I am wanting to make a plot with a secondary y axis, just like the 
matlab function plotyy does. Does anyone have any tips on how to do this 
with matplotlib?

Cheers,
Cory.


-- 
---------------------------------------------------
Cory Davis
Institute for Atmospheric and Environmental Science
Room 307, Crew Building, Kings Buildings,
University of Edinburgh. Edinburgh EH9 3JN
phone: +44 131 6505092
www: http://www.geos.ed.ac.uk/contacts/homes/cdavis

Jeff,

You're probably right, my numarray.__version__ = 0.9.  After updating numarray 
to 1.3.1 all the examples ran except randompoints.py.  Perhaps you knew this.  
After changing line 44 as below...


#      r = (m.projtran.rmajor/1000.)*get_dist(lon,lons[0:nob],lat,lats[0:nob])
      r = (m.projtran.rsphere/1000.)*get_dist(lon,lons[0:nob],lat,lats[0:nob])

randompoints.py ran to completion.  I'm not sure if it was an appropriate 
change but at least the example competed.  thanks Jeff...

Best,
Derrick

On Wed May 11 2005 01:40 pm, Jeff Whitaker wrote:
> Derrick Snowden wrote:
> > Hi all,
> >
> > I'm new to this product so my question involves installation issues
> > with Basemap.  I had no problem installing matplotlib and as far as I
> > could tell, there were no issues preventing the Basemap installation.
> > However, when I run the test scripts I get an error message that seems
> > to be related to cPickle.  Several of the example scripts yield the
> > same error, but not all.  Any suggestions?
> >
> > The message is included below and the platform I'm using is Fedora
> > core 2 linux.  Python version 2.3.3.
> >
> > Thanks for any suggestions,
> > Derrick
> >
> >
> > log of the error messages...
> >
> > /usr/lib/python2.3/site-packages/matplotlib/__init__.py:636:
> > UserWarning: Bad key "verbose.erro" on line 199 in
> > /home/snowden/.matplotlibrc
> >   warnings.warn('Bad key "%s" on line %d in %s' % (key, cnt, fname))
> > loaded rc file /home/snowden/.matplotlibrc
> > matplotlib version 0.80
> > verbose.level helpful
> > interactive is False
> > platform is linux2
> > numerix Numeric 23.3
> > font search path ['/usr/share/matplotlib']
> > loaded ttfcache file /home/snowden/.ttffont.cache
> > matplotlib data path /usr/share/matplotlib
> > backend GTKAgg version 2.2.0
> > Traceback (most recent call last):
> >   File "plotmap.py", line 11, in ?
> >     topodict = cPickle.load(open('etopo20.pickle','rb'))
> >   File "/usr/lib/python2.3/site-packages/numarray/generic.py", line
> > 160, in ClassicUnpickler
> >     self.__setstate__(state)
> >   File "/usr/lib/python2.3/site-packages/numarray/numarraycore.py",
> > line 492, in __setstate__
> >     self._type      = state["_type"]
> > AttributeError: ("'str' object has no attribute 'name'", <function
> > ClassicUnpickler at 0x40e435a4>, (<class
> > 'numarray.numarraycore.NumArray'>, {'_type': 'Float32', '_itemsize':
> > 4, '_shape': (1081,), '_bytestride': 4, '_byteoffset': 0, '_version':
> > '1.1', '_byteorder': 'big', '_data': <memory at 083f7568 with
> > size:4324 held by object 083f7548 aliasing object 00000000>,
> > '_strides': (4,)}))
>
> Derrick:  The example is trying to read a Pickle file with some data.  I
> think the problem may be that your numarray is too old.  New versions of
> numarray cannot read pickles created by very old versions of numarry,
> apparently.  Is your numarray older than 1.0?
>
> -Jeff

-- 
Derrick Snowden
PhOD/AOML/NOAA
4301 Rickenbacker Causeway
Miami, FL 33149
Office: 305.361.4322  Fax: 305.361.4392

Matt Newville wrote:
>>Mmh, the problem is that I don't know how to achieve this in a clean, 
>>distutils-based way.  I can't go changing the shebang line by hand, since I 
>>don't know where things will end up, and as far as I know there is no way to 
>>force this kind of behavior onto distutils.  Do you know any such incantation 
>>to achieve the desired result?
> 
> 
> (Sorry for not getting back to you on this -- conference all
> last week, still finding emails to answer).  I'd guess that for
> sys.platform == 'Darwin', you _could_ assume that you know where
> things will end up.

I'm a bit of a one-trick-pony (linux being my trick, and if that), so I'm 
afraid I'll have to ask for a bit of feedback from you and/or other OSX real 
gurus.  I worry about polluting setup.py with os-specific hacks (the stuff for 
win32 is ugly enough), and in OSX there's the issue of the Apple Python vs. 
the fink one vs. any other hand-installed one.

What happens if paths get hardcoded in there, and someone wants to install 
with some test python version they have living in 
/scratch/foo/bar/python2.5.0CVS... ?

Messing with distutils is a bit dangerous, because people expect that if they 
issue a certain command with one of the relocation flags (--home, --prefix), 
it will do the right thing.  Are you sure that your idea won't generate 
conflicts with such options, and across multiple python versions living in the 
same system?

I don't want to sound discouraging, but I am _very_ careful with tweaking the 
setup scripts.  They are really easy to break, so I won't touch them until I 
am _very_ convinced that the changes are really, really solid and properly 
take into account all the foreseable pitfalls.  And the problem with breaking 
setup.py, is that you typically find out about it only when some user with a 
sligthly unusual config comes back complaining about a broken system.  I'd 
like to avoid that if possible.

Cheers,

f

Derrick Snowden wrote:

> Hi all,
>
> I'm new to this product so my question involves installation issues 
> with Basemap.  I had no problem installing matplotlib and as far as I 
> could tell, there were no issues preventing the Basemap installation. 
> However, when I run the test scripts I get an error message that seems 
> to be related to cPickle.  Several of the example scripts yield the 
> same error, but not all.  Any suggestions?
>
> The message is included below and the platform I'm using is Fedora 
> core 2 linux.  Python version 2.3.3.
>
> Thanks for any suggestions,
> Derrick
>
>
> log of the error messages...
>
> /usr/lib/python2.3/site-packages/matplotlib/__init__.py:636: 
> UserWarning: Bad key "verbose.erro" on line 199 in 
> /home/snowden/.matplotlibrc
>   warnings.warn('Bad key "%s" on line %d in %s' % (key, cnt, fname))
> loaded rc file /home/snowden/.matplotlibrc
> matplotlib version 0.80
> verbose.level helpful
> interactive is False
> platform is linux2
> numerix Numeric 23.3
> font search path ['/usr/share/matplotlib']
> loaded ttfcache file /home/snowden/.ttffont.cache
> matplotlib data path /usr/share/matplotlib
> backend GTKAgg version 2.2.0
> Traceback (most recent call last):
>   File "plotmap.py", line 11, in ?
>     topodict = cPickle.load(open('etopo20.pickle','rb'))
>   File "/usr/lib/python2.3/site-packages/numarray/generic.py", line 
> 160, in ClassicUnpickler
>     self.__setstate__(state)
>   File "/usr/lib/python2.3/site-packages/numarray/numarraycore.py", 
> line 492, in __setstate__
>     self._type      = state["_type"]
> AttributeError: ("'str' object has no attribute 'name'", <function 
> ClassicUnpickler at 0x40e435a4>, (<class 
> 'numarray.numarraycore.NumArray'>, {'_type': 'Float32', '_itemsize': 
> 4, '_shape': (1081,), '_bytestride': 4, '_byteoffset': 0, '_version': 
> '1.1', '_byteorder': 'big', '_data': <memory at 083f7568 with 
> size:4324 held by object 083f7548 aliasing object 00000000>, 
> '_strides': (4,)}))
>
>
Derrick:  The example is trying to read a Pickle file with some data.  I 
think the problem may be that your numarray is too old.  New versions of 
numarray cannot read pickles created by very old versions of numarry, 
apparently.  Is your numarray older than 1.0?

-Jeff

-- 
Jeffrey S. Whitaker         Phone  : (303)497-6313
Meteorologist               FAX    : (303)497-6449
NOAA/OAR/CDC  R/CDC1        Email  : Jef...@no...
325 Broadway                Office : Skaggs Research Cntr 1D-124
Boulder, CO, USA 80303-3328 Web    : http://tinyurl.com/5telg

>>>>> "andrea" == andrea gavana <and...@ti...> writes:

    andrea> Is there a way to add an histogram to my subplot?

Make sure ax.hold(True) is set, and then call hist after plot

  ax.hold(True)
  ax.plot(something)
  ax.hist(something)

Should work...

JDH

Hi all,

I'm new to this product so my question involves installation issues with 
Basemap.  I had no problem installing matplotlib and as far as I could 
tell, there were no issues preventing the Basemap installation. 
However, when I run the test scripts I get an error message that seems 
to be related to cPickle.  Several of the example scripts yield the same 
error, but not all.  Any suggestions?

The message is included below and the platform I'm using is Fedora core 
2 linux.  Python version 2.3.3.

Thanks for any suggestions,
Derrick


log of the error messages...

/usr/lib/python2.3/site-packages/matplotlib/__init__.py:636: 
UserWarning: Bad key "verbose.erro" on line 199 in 
/home/snowden/.matplotlibrc
   warnings.warn('Bad key "%s" on line %d in %s' % (key, cnt, fname))
loaded rc file /home/snowden/.matplotlibrc
matplotlib version 0.80
verbose.level helpful
interactive is False
platform is linux2
numerix Numeric 23.3
font search path ['/usr/share/matplotlib']
loaded ttfcache file /home/snowden/.ttffont.cache
matplotlib data path /usr/share/matplotlib
backend GTKAgg version 2.2.0
Traceback (most recent call last):
   File "plotmap.py", line 11, in ?
     topodict = cPickle.load(open('etopo20.pickle','rb'))
   File "/usr/lib/python2.3/site-packages/numarray/generic.py", line 
160, in ClassicUnpickler
     self.__setstate__(state)
   File "/usr/lib/python2.3/site-packages/numarray/numarraycore.py", 
line 492, in __setstate__
     self._type      = state["_type"]
AttributeError: ("'str' object has no attribute 'name'", <function 
ClassicUnpickler at 0x40e435a4>, (<class 
'numarray.numarraycore.NumArray'>, {'_type': 'Float32', '_itemsize': 4, 
'_shape': (1081,), '_bytestride': 4, '_byteoffset': 0, '_version': 
'1.1', '_byteorder': 'big', '_data': <memory at 083f7568 with size:4324 
held by object 083f7548 aliasing object 00000000>, '_strides': (4,)}))

Hello NG,

    as usual, I am using wxPython + MatPlotLib to create nice interfaces
+ nice plots. However, I'm having a problem (probably I am unable to find=

the right code to do it) in putting together 2 plots. This is the situati=
on:

In some way, I have calculated a CDF of a Numeric array, and I can easily=

plot it using the sequence:

self.fig =3D Figure()        
self.canvas =3D FigureCanvas(self, -1, self.fig)

axdata =3D self.fig.add_subplot(111)
mp =3D axdata.plot(CDF,ArrayFromZeroToOne,'b-')

Now, I would like to add the histogram of my array to the same figure, bu=
t
I'm getting nowhere. The histogram is not displayed.
Note that I am *not* importing Pylab or similar, I use:

from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as Figure=
Canvas
from matplotlib.backends.backend_wx import NavigationToolbar2Wx
from matplotlib.figure import Figure

Is there a way to add an histogram to my subplot?

Thank you for every suggestion.

Andrea.

>>>>> "Andrew" == Andrew Dalke <da...@da...> writes:

    Andrew> A few weeks ago I asked about using matplotlib to make a
    Andrew> simple client-side image map for a web page.

Hmm, I missed this post somehow.  Sorry to have ignored you :-(  It
looks like you did just fine w/o me

    Andrew> I since figured out my problem.  I wrote an set of essays
    Andrew> on it.  The most relevant is at
    Andrew> http://www.dalkescientific.com/writings/diary/archive/2005/04/24/
    Andrew> interactive_html.html

A friend was just pestering me to add support for this for his
business.  Thanks for figuring it out!  The articles are very nice;
I'll be sure to link to them from the mpl web site.

A few comments: 

    Andrew> They can be used together, as you might have seen in my code from last time.

The link
http://www.dalkescientific.com/writings/diary/archive/2005/04/22/matplotlib
associated with the text "my code from last time" is stale.


  Andrew> Most image formats are in pixels, and the number of pixels
  Andrew> in an inch depends on the screen size, resolution, and even
  Andrew> the distance to the screen. The conversion to pixels is done
  Andrew> by the print_figure() call, which is why it takes the dpi
  Andrew> parameter. Looking at the library code I see that the
  Andrew> Figure() constructor also takes a dpi parameter. I don't
  Andrew> know when it's used.

It is used when building the GUI window (eg dpi should reflect your
screen dpi).  It is not used for hardcopy, because the print_figure
dpi setting overrides it.

  Andrew> I can't find any place in matplotlib that gives the final
  Andrew> image size in pixels. I think the right place is to have
  Andrew> print_figure() return a data structure with information
  Andrew> about what it just printed (image size, perhaps the number
  Andrew> of bytes). But it doesn't so I'll compute it myself.

A good idea.  Could I trouble you to fill out a support request at 
http://sourceforge.net/tracker/?group_id=80706&atid=560721 .  This is
something that takes more that just a minute to fix because it has to
be done on each backend, so having it on the support requests page
will help prevent us from forgetting to do it.

Thanks for the articles -- they are very helpful.

JDH

>>>>> "Florian" == Florian Lindner <mai...@xg...> writes:

    Florian> Hello, which interface is to prefer when using it from
    Florian> python scripts? Are they both offer the same
    Florian> functionality? Which one is more pythonic?  Where can I
    Florian> find examples for using the matplotlib classes? (I've
    Florian> only found a lot of examples for pylab)

It depends a bit on how you want to use matplotlib.  Interactively, eg
from a shell, the pylab interface is more efficient.  For generating
scripts in batch mode, eg on a web application server, or for building
a GUI, the matplotlib API is better because it gives you more control
and less magic.

See the FAQ "Is there any guide to using matplotlib with pythonic / OO
/API rather than the pylab interface?" for a few pointers to
resources, which I will soon update with a pointer to Andrew Dalke's
very nice recent article, hot off the presses, "matplotlib without a
GUI" at
http://www.dalkescientific.com/writings/diary/archive/2005/04/23/matplotlib_without_gui.html

JDH

On Wed, 11 May 2005, Florian Lindner apparently wrote: 
> which interface is to prefer when using it from python scripts? Are they both 
> offer the same functionality? Which one is more pythonic? 
> Where can I find examples for using the matplotlib classes? (I've only found a 
> lot of examples for pylab) 

http://matplotlib.sourceforge.net/faq.html#OO

hth,
Alan Isaac

Hello,
which interface is to prefer when using it from python scripts? Are they both 
offer the same functionality? Which one is more pythonic?
Where can I find examples for using the matplotlib classes? (I've only found a 
lot of examples for pylab)

Thanks,
Florian