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I've been trying to plot a pcolor over a contourf with a masked array in 
the pcolor so that parts of the contour will show through underneath, 
but whenever I try to do this the pcolor wipes out the contourf. I can 
do this fine with a contourf over another contourf, but I'm plotting 
model topography, and I would really prefer to leave the discretization 
visible instead of showing contourf's interpolation. Any way to get a 
pcolor to plot over a contourf without wiping out the contourf beneath it?
Jordan

On 8/31/07, Romain Bignon <ro...@in...> wrote:
> Hello,
>
> I want to get pixels position of a Text object on my imagine, but there isn't
> any methods of this class to get them.
>
> How can I do ?
You can use the t.get_window_extent() method of the text object, with
the caveat that this
only works *after* the canvas has been drawn, so you need to force a
draw first. Makre sure you use the same DPI in the figure and savefig
commands if you need these coords for working with hardcopy
from pylab import figure, show
fig = figure(figsize=(6,6), dpi=72)
ax = fig.add_subplot(111)
ax.plot([1,2,3])
t = ax.text(1,2,'hi')
fig.canvas.draw()
left, bottom, width, height = t.get_window_extent().get_bounds()
print left, bottom, width, height
fig.savefig('test', dpi=72) # make sure you use the same DPI if you save
show()

Hi,
is it somehow possible to have a hatch in parts of the background, which
would achieve something like this pseudo-parameter to axvspan
pylab.axvspan(2, 10, hatch='//')?
TIA
Christian

OK, I've got it. Previously, I checked the quality of the output image
by two means: by visual inspection in gv and by checking the size of the
output eps images. 
I was puzzled by the different sizes of the images at magnification 1.
Also, convert produces much larger eps files. 
When the size of the output image is set to 6.3246cm (1494px at 600dpi)
and the axes are turned off, both versions appear identical when
printed. 
Thanks for your help,
petr
On Thu, 2007年08月30日 at 20:35, Jouni K. Seppänen wrote:
> I don't see a big difference between test-600.eps and test-convert.eps
> when viewed in gv with magnification 10 and 0.1, respectively. Obviously
> there is some resampling in test-600.eps: your source image is 1494 by
> 1494 pixels large, which at 600 dpi is larger than the 5 by 5 cm figure
> created by the script (and the axes are even smaller). test-convert.eps
> has a bounding box of 0 0 1494 1494, so obviously it is a non-resampled
> image at 72 dpi.
> 
> If the problem you are alluding to is in the resampling, perhaps 
> varying the interpolation algorithm will produce a better result? 
> See the docstring of imshow.
> 
> To get a non-resampled image, figimage should work, but it doesn't seem
> to understand PIL images yet...

Hello,
I want to get pixels position of a Text object on my imagine, but there isn't 
any methods of this class to get them.
How can I do ?
Regards,
-- 
Romain Bignon - http://progs.coderz.info
http://www.inl.fr

Hoi,
There is still MPL's polyfit function and I have to admit that Steve
Schmerler's solution looks better that mine, but I've pasted a quick &
dirty solution here:
http://www.python-forum.de/topic-8363.html
It shows the use of polyfit as well as (almost) Steve's approach.
Further examples on linear regression and polynomal regression can be
found in http://matplotlib.sourceforge.net/users_guide_0.90.0.pdf
Also, you might want to have a closer look on the scipy web page:
http://www.scipy.org/ .
Cheers
Christian