matplotlib-users Mailing List for matplotlib (Page 15)

Also, I am not sure how to use alan's code.

If I try:

ec = empirical_cdf(my_data)
plt.plot(ec)

it doesn't actually look like a cdf

On Fri, Jul 9, 2010 at 10:17 AM, per freem <per...@gm...> wrote:
> How does Alan's code compare with using cumfreq and then plotting its
> result?  Is the only difference that cumfreq bins the data?
>
> On Fri, Jul 9, 2010 at 10:12 AM, Robert Kern <rob...@gm...> wrote:
>> On 7/9/10 10:02 AM, per freem wrote:
>>> I'd like to clarify: I want the empirical cdf, but I want it to be
>>> normalized.  There's a normed=True option to plt.hist but how can I do
>>> the equivalent for CDFs?
>>
>> There is no such thing as a normalized empirical CDF. Or rather, there is no
>> such thing as an unnormalized empirical CDF.
>>
>> Alan's code is good. Unless if you have a truly staggering number of points,
>> there is no reason to bin the data first.
>>
>> --
>> Robert Kern
>>
>> "I have come to believe that the whole world is an enigma, a harmless enigma
>>  that is made terrible by our own mad attempt to interpret it as though it had
>>  an underlying truth."
>>   -- Umberto Eco
>>
>>
>> ------------------------------------------------------------------------------
>> This SF.net email is sponsored by Sprint
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>> _______________________________________________
>> Matplotlib-users mailing list
>> Mat...@li...
>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>>
>

How does Alan's code compare with using cumfreq and then plotting its
result?  Is the only difference that cumfreq bins the data?

On Fri, Jul 9, 2010 at 10:12 AM, Robert Kern <rob...@gm...> wrote:
> On 7/9/10 10:02 AM, per freem wrote:
>> I'd like to clarify: I want the empirical cdf, but I want it to be
>> normalized.  There's a normed=True option to plt.hist but how can I do
>> the equivalent for CDFs?
>
> There is no such thing as a normalized empirical CDF. Or rather, there is no
> such thing as an unnormalized empirical CDF.
>
> Alan's code is good. Unless if you have a truly staggering number of points,
> there is no reason to bin the data first.
>
> --
> Robert Kern
>
> "I have come to believe that the whole world is an enigma, a harmless enigma
>  that is made terrible by our own mad attempt to interpret it as though it had
>  an underlying truth."
>   -- Umberto Eco
>
>
> ------------------------------------------------------------------------------
> This SF.net email is sponsored by Sprint
> What will you do first with EVO, the first 4G phone?
> Visit sprint.com/first -- http://p.sf.net/sfu/sprint-com-first
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>

On 7/9/10 10:02 AM, per freem wrote:
> I'd like to clarify: I want the empirical cdf, but I want it to be
> normalized.  There's a normed=True option to plt.hist but how can I do
> the equivalent for CDFs?

There is no such thing as a normalized empirical CDF. Or rather, there is no 
such thing as an unnormalized empirical CDF.

Alan's code is good. Unless if you have a truly staggering number of points, 
there is no reason to bin the data first.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco

I'd like to clarify: I want the empirical cdf, but I want it to be
normalized.  There's a normed=True option to plt.hist but how can I do
the equivalent for CDFs?

On Fri, Jul 9, 2010 at 9:14 AM, Alan G Isaac <ala...@gm...> wrote:
> On 7/9/2010 12:02 AM, per freem wrote:
>>  How can I plot the empirical CDF of an array of numbers in matplotlib
>>  in Python?
>
>
> I recalled David Huard posted the below,
> which apparently was once in the sandbox...
> hth,
> Alan Isaac
>
> def empiricalcdf(data, method='Hazen'):
>     """Return the empirical cdf.
>
>     Methods available (here i goes from 1 to N)
>         Hazen:       (i-0.5)/N
>         Weibull:     i/(N+1)
>         Chegodayev:  (i-.3)/(N+.4)
>         Cunnane:     (i-.4)/(N+.2)
>         Gringorten:  (i-.44)/(N+.12)
>         California:  (i-1)/N
>
>     :see:
> http://svn.scipy.org/svn/scipy/trunk/scipy/sandbox/dhuard/stats.py
>     :author: David Huard
>     """
>     i = np.argsort(np.argsort(data)) + 1.
>     nobs = len(data)
>     method = method.lower()
>     if method == 'hazen':
>         cdf = (i-0.5)/nobs
>     elif method == 'weibull':
>         cdf = i/(nobs+1.)
>     elif method == 'california':
>         cdf = (i-1.)/nobs
>     elif method == 'chegodayev':
>         cdf = (i-.3)/(nobs+.4)
>     elif method == 'cunnane':
>         cdf = (i-.4)/(nobs+.2)
>     elif method == 'gringorten':
>         cdf = (i-.44)/(nobs+.12)
>     else:
>         raise 'Unknown method. Choose among Weibull, Hazen, Chegodayev,
> Cunnane, Gringorten and California.'
>     return cdf
>
>
>
>
> ------------------------------------------------------------------------------
> This SF.net email is sponsored by Sprint
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> _______________________________________________
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> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>

Good day!
Could You please tell me how can I get axises autoscaling in the 
animated plot example. I've take an example and have modifyed it 
slightly so the second line in plot gets out of bounding box during 
animation. What I need is autoscaling of axises during animation. Please 
point mee what I have to do.

Thanks a lot!

Hereafter a modifyed example:
--------------------------------------------------------------------

# For detailed comments on animation and the techniqes used here, see
# the wiki entry http://www.scipy.org/Cookbook/Matplotlib/Animations

import sys

from matplotlib.figure import Figure
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as 
FigureCanvas

from PyQt4 import QtGui

ITERS = 100

import numpy as np
import time

class BlitQT(FigureCanvas):
     def __init__(self):
         FigureCanvas.__init__(self, Figure())

         self.ax = self.figure.add_subplot(111)
         self.ax.grid()
         self.draw()

         self.old_size = self.ax.bbox.width, self.ax.bbox.height
         self.ax_background = self.copy_from_bbox(self.ax.bbox)
         self.cnt = 0

         self.x = np.arange(0,2*np.pi,0.01)
         self.sin_line, = self.ax.plot(self.x, np.sin(self.x), 
animated=True)
         self.cos_line, = self.ax.plot(self.x, np.cos(self.x), 
animated=True)
         self.draw()

         self.tstart = time.time()
         self.startTimer(10)

     def timerEvent(self, evt):
         current_size = self.ax.bbox.width, self.ax.bbox.height
         if self.old_size != current_size:
             self.old_size = current_size
             self.ax.clear()
             self.ax.grid()
             self.draw()
             self.ax_background = self.copy_from_bbox(self.ax.bbox)

         self.restore_region(self.ax_background, bbox=self.ax.bbox)

         # update the data
         self.sin_line.set_ydata(np.sin(self.x+self.cnt/10.0))
         self.cos_line.set_ydata((self.x+self.cnt)/50.0)
         # just draw the animated artist
         self.ax.draw_artist(self.sin_line)
         self.ax.draw_artist(self.cos_line)
         # just redraw the axes rectangle
         self.blit(self.ax.bbox)

         if self.cnt == 0:
             # TODO: this shouldn't be necessary, but if it is excluded the
             # canvas outside the axes is not initially painted.
             self.draw()
         if self.cnt==ITERS:
             # print the timing info and quit
             print 'FPS:' , ITERS/(time.time()-self.tstart)
             sys.exit()
         else:
             self.cnt += 1

app = QtGui.QApplication(sys.argv)
widget = BlitQT()
widget.show()

sys.exit(app.exec_())

On 7/9/2010 12:02 AM, per freem wrote:
>  How can I plot the empirical CDF of an array of numbers in matplotlib
>  in Python?


I recalled David Huard posted the below,
which apparently was once in the sandbox...
hth,
Alan Isaac

def empiricalcdf(data, method='Hazen'):
     """Return the empirical cdf.

     Methods available (here i goes from 1 to N)
         Hazen:       (i-0.5)/N
         Weibull:     i/(N+1)
         Chegodayev:  (i-.3)/(N+.4)
         Cunnane:     (i-.4)/(N+.2)
         Gringorten:  (i-.44)/(N+.12)
         California:  (i-1)/N

     :see:
http://svn.scipy.org/svn/scipy/trunk/scipy/sandbox/dhuard/stats.py
     :author: David Huard
     """
     i = np.argsort(np.argsort(data)) + 1.
     nobs = len(data)
     method = method.lower()
     if method == 'hazen':
         cdf = (i-0.5)/nobs
     elif method == 'weibull':
         cdf = i/(nobs+1.)
     elif method == 'california':
         cdf = (i-1.)/nobs
     elif method == 'chegodayev':
         cdf = (i-.3)/(nobs+.4)
     elif method == 'cunnane':
         cdf = (i-.4)/(nobs+.2)
     elif method == 'gringorten':
         cdf = (i-.44)/(nobs+.12)
     else:
         raise 'Unknown method. Choose among Weibull, Hazen, Chegodayev,
Cunnane, Gringorten and California.'
     return cdf

On Fri, Jul 9, 2010 at 7:25 AM, Karianne Holhjem
<kar...@as...> wrote:

> Regarding numpy - what you say is intersting. I couldn't find any such
> problems in my google-searches. I am running version 1.2.1:
> [karianneholhjem:/] karianne% python -c 'import numpy; print numpy.__version__'
> 1.2.1

Can you try upgrading numpy to the latest released version?  This is
likely your problem.  I would rm -rf the old numpy in your
site-packages directory and upgrade to 1.4.1


https://sourceforge.net/projects/numpy/files/NumPy/1.4.1/numpy-1.4.1-py2.5-python.org.dmg/download

Are you using python.org python or Apple python -- it appears the
installer above is for python.org python

JDH

Hi,

I changed the script to what you suggested and this is the output:
[karianneholhjem:~] karianne% python bla.py --verbose-helpful
$HOME=/Users/karianne
CONFIGDIR=/Users/karianne/.matplotlib
matplotlib data path /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/mpl-data
loaded rc file /Users/karianne/.matplotlib/matplotlibrc
matplotlib version 1.0.0
verbose.level helpful
interactive is False
units is False
platform is darwin
Bus error

I get the same output when commenting out either line 2 or 3. 
(/Users/karianne/.matplotlib/matplotlibrc is just a link to 
/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/mpl-data/matplotlibrc 
as was in my previous output.)


Regarding numpy - what you say is intersting. I couldn't find any such 
problems in my google-searches. I am running version 1.2.1:
[karianneholhjem:/] karianne% python -c 'import numpy; print numpy.__version__'
1.2.1

I couldn't find the version requirements in the README file so I probably 
found the wrong README
(/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/numpy/README.txt). 
It did provide a way of testing numpy, I don't know if it's interesting 
but here is the output:

[karianneholhjem:/] karianne% python -c 'import numpy; numpy.test()'
Running unit tests for numpy
NumPy version 1.2.1
NumPy is installed in 
/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/numpy
Python version 2.5.2 (r252:60911, Feb 22 2008, 07:57:53) [GCC 4.0.1 (Apple 
Computer, Inc. build 5363)]
nose version 0.11.3
...........................................................................................................................................................................................................................................................................................................................................................................................................................................................K................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
----------------------------------------------------------------------
Ran 1740 tests in 8.691s

OK (KNOWNFAIL=1)

Is there any more information I can provide to give you clues as of why 
pyplot and pylab aren't working? Thank you for your help so far, I did a 
course on python/numpy/matplotlib and I would really like to use 
matplotlib as it is a really powerful plotting tool!

cheers,
Karianne


On Thu, 8 Jul 2010, John Hunter wrote:

> On Thu, Jul 8, 2010 at 5:50 AM, Karianne Holhjem
> <kar...@as...> wrote:
> > Hi,
> >
> > I'm having trouble getting pyplot and pylab to work on my Mac v.10.4.11
> > (Tiger). I've tried searching in both google and different macusers
> > forums, but haven't found an answer to my problems. If I have overlooked a
> > webpage please send me a link to the solution.
> >
> > To download matplotlib I have downloaded the dmg package from the official
> > matplotlib page
> > http://sourceforge.net/projects/matplotlib/files/matplotlib/matplotlib-1.0/http://sourceforge.net/projects/matplotlib/files/matplotlib/matplotlib-1.0/
> >
> > and it seems to install fine. However, I cannot use neither pyplot nor
> > pylab:
> 
> 
> You're on the right track with the debugging information you are
> trying to provide.  One problem is in your script bla.py.  You do
> 
>   import matplotlib as mpl
>   import mpl.pyplot
>   import mpl.pylab
> 
> but you need to do
> 
>   import matplotlib as mpl
>   import matplotlib.pyplot
>   import matplotlib.pylab
> 
> This won't fix your segfault, but it may help you get get better
> debugging information.
> 
> My first guess is a numpy version conflict -- what version are you
> running?  You can check the version requirements of the OSX installer
> in the README that is provides.  Many recent versions of numpy are not
> ABI compatible, unfortunately.
> 
> JDH
> 

Hi,

I have some troubles updating a contour plot. I reduced my code to a simple example to reproduce the problem: 

[code]
from pylab *
import scipy as sp

x=sp.arange(0,2*sp.pi,0.1)
X,Y=sp.meshgrid(x,x)
f1=sp.sin(X)+sp.sin(Y)
f2=sp.cos(X)+sp.cos(Y)

figure()
C=contourf(f1)
show()

C.set_array(f2)
draw()
[\code]

The problem is that C.set_array(f2) does not show any effect, not even after I call draw(). Shouldn't the array f2 be displayed after that? In comparison, the following code using imshow instead of contour works well:

[code]
figure()
I=imshow(f1)
show()
I.set_data(f2)
draw()
[\code]

What do I need to do to update an existing contour plot with new data?

Greetings
Johannes

Hi,

I posted this to stackoverflow
(http://stackoverflow.com/questions/3190798/scale-legend-box-border-dashed-and-dotted-lines-when-the-figure-size-is-changed),
but didn't get any answer, so here goes again:

I'm trying to use matplotlib to prepare some figures for publication.
In order to make the font sizes match the text of the manuscript I'm
trying to create the figure in the final size to begin with, so that I
avoid scaling the figure when inserting it into the manuscript.

The problem I'm having is that as the figure is then pretty small, I
can scale font sizes, axis sizes, line widths etc., but what I've been
unable to figure out is how to scale dashed or dotted lines, as well
as the thickness of the legend border box. For a simplified and
somewhat exaggerated example, consider


#!/usr/bin/python

small = True


from matplotlib import use
use('pdf')

from matplotlib import rc
rc('ps', usedistiller='xpdf')
rc('text', usetex=True)

if small:
   figsize = (1.0, 0.5)
   rc('font', size=2)
   rc('axes', labelsize=2, linewidth=0.2)
   rc('legend', fontsize=2, handlelength=10)
   rc('xtick', labelsize=2)
   rc('ytick', labelsize=2)
   rc('lines', lw=0.2, mew=0.2)
   rc('grid', linewidth=0.2)
else:
   figsize = (8,8)

import numpy as np

x = np.arange(0, 10, 0.001)
y = np.sin(x)

import matplotlib.pyplot as plt
f = plt.figure(figsize=figsize)
a = f.add_subplot(111)
a.plot(x, y, '--', label='foo bar')
a.legend()
f.savefig('mplt.pdf')

If you change the first executable line to small = False you can see
how it should look in "normal" size. Compared to the normal size, the
small plot suffers from a legend box with too thick borders, and the
dashed line is too coarse, i.e. too long dashes and too long distance
between the dashes.

So my question is, is there a way to fix these two problems?

The matplotlib version I'm using is 0.99.1.2 on ubuntu 10.04 amd64.


-- 
Janne Blomqvist

Dear Matplotlib developers,

first of all my congratulations with the excellent 1.0 release, great work!

I currently use a custom compiled 64 bit version of Python 2.6.
But I would like to switch to the prebuild binaries for Python 2.7 as
soon as possible.
Are there any plans for supplying matplotlib 1.x dmg installers for
Python 2.7 (including 64 bit support on OSX)?

Kind regards,

Pim Schellart

P.S. I quickly tried compiling matplotlib from source against Python
2.7 which worked (after setting PREFIX=/usr/local and PYVERSION=2.7 in
make.osx and compiling with sudo make -f make.osx fetch deps mpl_build
mpl_install && sudo python setup.py install) but failed with a
segfault on import.

How can I plot the empirical CDF of an array of numbers in matplotlib
in Python? I'm looking for the cdf analog of pylab's "hist" function.

One thing I can think of is:

from scipy.stats import cumfreq
a = array([...]) # my array of numbers
num_bins =  20
b = cumfreq(a, num_bins)
plt.plot(b)

Is that correct though? Is there an easier/better way?

thanks.

Yes, I believe so.  I believe it is possible to create the axes with
navigation  disabled so that their callbacks are never connected.  Then, you
can use the same callback system to trigger the axes pan and zoom on your
own controls.

http://matplotlib.sourceforge.net/users/event_handling.html
http://matplotlib.sourceforge.net/api/axes_api.html

(particularly about disconnect() and drag_pan() and friends).

Maybe someone else knows of an example?

Ben Root

On Thu, Jul 8, 2010 at 4:55 PM, German Ocampo <ger...@gm...> wrote:

> Good afternoon
>
> I'm working in an application with a simple figure embbebed in a QT
> Dialog. I want to instead of use the navigation toolbar of matplotlib,
> have some Qt push buttons in the form, that allow to perform the  Zoom
> and Pan. Is it possible to do it?
>
> Many thanks for your help
>
> German
>
>
> ------------------------------------------------------------------------------
> This SF.net email is sponsored by Sprint
> What will you do first with EVO, the first 4G phone?
> Visit sprint.com/first -- http://p.sf.net/sfu/sprint-com-first
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>

Hello,

I keep getting the error "ValueError: Need more than 1 value to unpack" 
every time I try to use the line ax.plot_wireframe(myArray[:,0], 
myArray[:,1], myArray[:,2])

What does that error mean?

Thanks,
Shir

Good afternoon

I'm working in an application with a simple figure embbebed in a QT
Dialog. I want to instead of use the navigation toolbar of matplotlib,
have some Qt push buttons in the form, that allow to perform the  Zoom
and Pan. Is it possible to do it?

Many thanks for your help

German

In article <0D8...@gm...>,
 Edward Barnard <edb...@gm...> 
 wrote:

> Hi All
> 
> I had a problem installing matplotlib 1.0.0 on MacOS X 10.6 using python.org 
> 2.6.5 with the binary installer (dmg). When importing pylab, datautils was 
> missing. I fixed that by easy_installing python-dateutils, but it seems like 
> it should be included in the installer or listed in the install requirements.
> 
> Thanks for a great piece of software!
> 
> -Ed
> 
> 
> 
> ------------------------------------------------------------------------------
> This SF.net email is sponsored by Sprint
> What will you do first with EVO, the first 4G phone?
> Visit sprint.com/first -- http://p.sf.net/sfu/sprint-com-first

I built the installer without dateutil and pytz packages.

At John Hunter's request I made new installers that do install these 
packages. I believe the new installers are now being served, so try 
downloading the installer and running it again.

Beware: the new installer always installs the versions it has; if you 
have a newer pytz or dateutil you want to keep, reinstall it afterwards 
or move it out of site-packages during the matplotlib install.

In article <A94...@tu...>,
 Shir Livne <shi...@tu...> wrote:

> Hi,
> 
> I downloaded the files from the site, but when i type "import  
> matplotlib" in python, it responds with "ImportError: No module named  
> matplotlib"
> 
> Does anyone mind going through the download steps for me? I probably  
> forgot something simple.

What file did you download?

If it was a binary installer, then which python are you using (open a 
Terminal and type "which python"). You should see a path starting with 
/Library, NOT with /System/Library.

If the path starts with /System/Library then that explains your problem: 
you are using the built-in python instead of the python from python.org 
(though the binary *may* work with other 3rd party pythons as well, e.g. 
Enthought or ActiveState).

So, the steps are:
- Download and install a suitable python from <http://python.org> (I 
recommend 2.6.x, but 2.5.x is also fine; we don't have a matplotlib 
binary for 2.7 yet because it is so new)
- Download and install the matching matplotlib Mac binary (for Python 
2.5 or 2.6).

Regards,

-- Russell

On Thu, Jul 8, 2010 at 5:50 AM, Karianne Holhjem
<kar...@as...> wrote:
> Hi,
>
> I'm having trouble getting pyplot and pylab to work on my Mac v.10.4.11
> (Tiger). I've tried searching in both google and different macusers
> forums, but haven't found an answer to my problems. If I have overlooked a
> webpage please send me a link to the solution.
>
> To download matplotlib I have downloaded the dmg package from the official
> matplotlib page
> http://sourceforge.net/projects/matplotlib/files/matplotlib/matplotlib-1.0/http://sourceforge.net/projects/matplotlib/files/matplotlib/matplotlib-1.0/
>
> and it seems to install fine. However, I cannot use neither pyplot nor
> pylab:


You're on the right track with the debugging information you are
trying to provide.  One problem is in your script bla.py.  You do

  import matplotlib as mpl
  import mpl.pyplot
  import mpl.pylab

but you need to do

  import matplotlib as mpl
  import matplotlib.pyplot
  import matplotlib.pylab

This won't fix your segfault, but it may help you get get better
debugging information.

My first guess is a numpy version conflict -- what version are you
running?  You can check the version requirements of the OSX installer
in the README that is provides.  Many recent versions of numpy are not
ABI compatible, unfortunately.

JDH

On Sun, Jul 4, 2010 at 8:38 PM, Benjamin Root <ben...@ou...> wrote:
> Jeremy,
>
> The pcolor function can take a vmin and a vmax parameter if you wish to
> control the colorscaling.  In addition, you can use a special array
> structure called a "masked array" to have pcolor ignore "special" values.
> Assuming your data is 'vals':
>
> vals_masked = numpy.ma.masked_array(vals, vals == 0.0)
>
> Note that depending on your situation, doing an equality with with a
> floating point  value probably isn't very reliable, so be sure to test and
> modify to suit your needs.  'vals_masked' can then be passed to pcolor
> instead of vals.

Yes, I think this is exactly what I need.  Thanks!

Jeremy

Caught by the default Reply-to...


---------- Forwarded message ----------
From: Scott Sinclair <sco...@gm...>
Date: 8 July 2010 13:46
Subject: Re: [Matplotlib-users] plotting irregular spaced data
To: Ross Williamson <ros...@gm...>


>On 8 July 2010 00:15, Ross Williamson <ros...@gm...> wrote:
> I have a set of 2d data (2d array) z
> (100x100) which I need to plot - I have a nominal set of x and y
> positions say:
>
> x = linspace(0,100)
> y = linspace(0,100)
>
> Now the actual positions of the points in z are given by the following:
>
> u,v = meshgrid(x,y)
>
> phi = arctan2(v,u)
> theta = arcsin(u/cos(phi))
>
> so I have three 2d arrays (100x100) which describe the postion
> (phi,theta) of the points in z
>
> How do I go about plotting these say using imshow?

If your z are actually values at points in (phi, theta), you might
find it easier to use scatter().

>>> import matplotlib.pyplot as plt
>>> plt.scatter(phi.ravel(), theta.ravel(), c=z.ravel(), edgecolors='none')
>>> plt.colorbar()

Cheers,
Scott

Hi,

I'm having trouble getting pyplot and pylab to work on my Mac v.10.4.11 
(Tiger). I've tried searching in both google and different macusers 
forums, but haven't found an answer to my problems. If I have overlooked a 
webpage please send me a link to the solution.

To download matplotlib I have downloaded the dmg package from the official 
matplotlib page
http://sourceforge.net/projects/matplotlib/files/matplotlib/matplotlib-1.0/http://sourceforge.net/projects/matplotlib/files/matplotlib/matplotlib-1.0/

and it seems to install fine. However, I cannot use neither pyplot nor 
pylab:

[kariannelap:~] karianne% python
Python 2.5.2 (r252:60911, Feb 22 2008, 07:57:53)
[GCC 4.0.1 (Apple Computer, Inc. build 5363)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import matplotlib as mpl
>>> import mpl.pyplot
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named mpl.pyplot
>>> import mpl.pylab
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named mpl.pylab
>>> import pylab
Bus error

I tried the clean rebuild and reinstall described on this page:

http://matplotlib.sourceforge.net/faq/installing_faq.html#cleanly-rebuild-and-reinstall-everything

and re-installed without any change. So then I tried deleting all
matplotlib and pylab files and dirs and re-installed, again without
results. I also tried this installation method without success

easy_install matplotlib
Processing matplotlib
error: Not a recognized archive type: matplotlib

Some more info:

[kariannelap:~] karianne% uname -a
Darwin karianneholhjem.local 8.11.1 Darwin Kernel Version 8.11.1: Wed Oct 10 18:23:28 PDT 2007; root:xnu
-792.25.20~1/RELEASE_I386 i386 i386

[kariannelap:~] karianne% python -c 'import matplotlib; print 
matplotlib.__version__'
1.0.0

Regarding the matplotlibrc file I have tried both the default
backend      : TkAgg
as well as
backend      : WxAgg
since some webpages indicated that might be a problem.

Finally, I wrote a little script called bla.py

import matplotlib as mpl
import mpl.pyplot
import mpl.pylab

and ran it

[kariannelap:~] karianne% python bla.py --verbose-helpful
$HOME=/Users/karianne
CONFIGDIR=/Users/karianne/.matplotlib
matplotlib data path 
/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matpl
otlib/mpl-data
loaded rc file 
/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/
mpl-data/matplotlibrc
matplotlib version 1.0.0
verbose.level helpful
interactive is False
units is False
platform is darwin
Traceback (most recent call last):
  File "bla.py", line 2, in <module>
    import mpl.pyplot
ImportError: No module named mpl.pyplot

When commenting out line 2 in the scrip this is the output I got:
$HOME=/Users/karianne
CONFIGDIR=/Users/karianne/.matplotlib
matplotlib data path 
/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matpl
otlib/mpl-data
loaded rc file 
/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/
mpl-data/matplotlibrc
matplotlib version 1.0.0
verbose.level helpful
interactive is False
units is False
platform is darwin
Traceback (most recent call last):
  File "bla.py", line 3, in <module>
    import mpl.pylab
ImportError: No module named mpl.pylab

Can someone please tell me what I am doing wrong or which files I should 
delete to make this work? I have had bad experiences with fink so I prefer 
not using it.

cheers,
Karianne

Thanks that was it.

Cleared it all out and installed tk-dev.

Then it came up with a error about unable to find -ltk8.5. Checked whether I
had tk8.5 installed and that was fine so I installed tk8.5-dev.

Cleaned again recompiled and it all seems to be fine.

Thanks


>

>On 7 July 2010 19:02, Eric Firing <ef...@ha...> wrote:
> On 07/07/2010 05:01 AM, Benjamin Root wrote:
>> Samuel,
>>
>> Fortunately, matplotlib keeps all of the files that it compiles with the
>> python files that it installs.  On Ubuntu, I believe that the
>> installation directory was /usr/lib/python2.?/dist-packages/matplotlib*
>
> ubuntu 8.04 was still using site-packages; the switch to dist-packages
> was in 9.10, if I remember correctly.  8.04 uses python 2.5.
>
> Also check the /usr/local path along with the /usr path. I'm not sure
> whether the installation from source put things by default in /usr or
> /usr/local.

You can check where your matplotlib is installed with

$ python -c "import matplotlib; print matplotlib"

Cheers,
Scott

imshow requires the data to be regularly spaced.  use pcolor instead.

Also, to be clear, pcolor() can take 1-D X and Y arguments, but only if it
is regular.  If the coordinates are irregular, then you need to use 2D X and
Y arguments.

Ben Root

On Wed, Jul 7, 2010 at 5:15 PM, Ross Williamson <
ros...@gm...> wrote:

> Hi Everyone
>
> I think I'm being dumb but I have a set of 2d data (2d array) z
> (100x100) which I need to plot - I have a nominal set of x and y
> positions say:
>
> x = linspace(0,100)
> y = linspace(0,100)
>
> Now the actual positions of the points in z are given by the following:
>
> u,v = meshgrid(x,y)
>
> phi = arctan2(v,u)
> theta = arcsin(u/cos(phi))
>
> so I have three 2d arrays (100x100) which describe the postion
> (phi,theta) of the points in z
>
> How do I go about plotting these say using imshow?
>
> Cheers
>
> Ross
>
> --
> Ross Williamson
> University of Chicago
> Department of Astronomy & Astrophysics
> 773-834-9785 (office)
> 312-504-3051 (Cell)
>
>
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>

Hi Everyone

I think I'm being dumb but I have a set of 2d data (2d array) z
(100x100) which I need to plot - I have a nominal set of x and y
positions say:

x = linspace(0,100)
y = linspace(0,100)

Now the actual positions of the points in z are given by the following:

u,v = meshgrid(x,y)

phi = arctan2(v,u)
theta = arcsin(u/cos(phi))

so I have three 2d arrays (100x100) which describe the postion
(phi,theta) of the points in z

How do I go about plotting these say using imshow?

Cheers

Ross

-- 
Ross Williamson
University of Chicago
Department of Astronomy & Astrophysics
773-834-9785 (office)
312-504-3051 (Cell)