matplotlib-users Mailing List for matplotlib

Eric Firing wrote:
>
> Maybe contour, contourf, and any similar plotting commands that do not 
> support zorder as a kwarg should do so? I am not sure if this is 
> needed often enough to warrant the extra code and documentation.
I can't speak for other people, but I use this kind of functionality in 
nearly every plot I do. Usually I contourf a field in 4-level 
greyscale, then contour over that to make 8 contour levels, then 
contourf over _that_ to mask land points (I run models so I have 'land' 
arrays I can use for this). Sometimes I them put polygons (sometimes 
transparent) over that to highlight regions. Usually how I've been 
doing this is by going in to illustrator and manually altering the 
stacking of the plot elements. Ideally how I wish it worked was that 
the default zorder was set by a counter, so the oldest plots on an axis 
would be buried under the newer ones.
Jordan

Jordan Dawe wrote:
>> pc = contour(random.rand(10,10))
>> pcf = contourf(random.rand(10,10), cmap=cm.gray)
>> # now the contours are on top
>>
>> for l in pc.collections:
>> l.set_zorder(-100)
>>
>> draw()
>> # now the contours are on the bottom
> 
> Well, that's certainly kludgey, but it worked great. Thanks.
Maybe contour, contourf, and any similar plotting commands that do not 
support zorder as a kwarg should do so? I am not sure if this is needed 
often enough to warrant the extra code and documentation.
Eric

>
> pc = contour(random.rand(10,10))
> pcf = contourf(random.rand(10,10), cmap=cm.gray)
> # now the contours are on top
>
> for l in pc.collections:
> l.set_zorder(-100)
>
> draw()
> # now the contours are on the bottom
Well, that's certainly kludgey, but it worked great. Thanks.
Jordan

I have a plot that is divided into four subplots.
pylab.figure()
pylab.subplot(221)
pylab.plot(a,b,"k-")
pylab.subplot(222)
pylab.plot(a,b,"k-")
pylab.subplot(223)
pylab.plot(a,b,"k-")
pylab.subplot(224)
pylab.plot(a,b,"k-")
I would like to add a title to the entire plot, but pylab.title() only
applies to the most recent subplot. I have tried
pylab.figure()
pylab.subplot(111)
pylab.title("Title Here")
pylab.subplot(221)
pylab.plot(a,b,"k-")
pylab.subplot(222)
pylab.plot(a,b,"k-")
pylab.subplot(223)
pylab.plot(a,b,"k-")
pylab.subplot(224)
pylab.plot(a,b,"k-")
but this does not work as I do not create a plot for
the subplot(111) instance. Is there some way of getting
the type of title I want easily?
Cheers
 Tommy

On Jan 24, 2008, at 8:11 AM, Jordan Dawe wrote:
> However, when I do this the result is the two contour plots are 
> drawn on
> top of the contourf plots no matter what. How do I hide the contours
> under a contourf?
zorder.
It won't really matter what order you plot, as long as you set the 
zorder of the objects to the order you want. However, there is no 
set_zorder for the whole contour, rather just for each element in the 
collection. Observe:
pc = contour(random.rand(10,10))
pcf = contourf(random.rand(10,10), cmap=cm.gray)
# now the contours are on top
for l in pc.collections:
 l.set_zorder(-100)
draw()
# now the contours are on the bottom
I guess the advantage is that you could pick and choose which 
contours to expose:
for l in pcf.collections[::2]:
 l.set_zorder(-1000)
draw()
# woven contours and contourfs...
-Rob
----
Rob Hetland, Associate Professor
Dept. of Oceanography, Texas A&M University
http://pong.tamu.edu/~rob
phone: 979-458-0096, fax: 979-845-6331

Ok, I've spent a while searching through the mailing list archives and I 
can't find an answer for this relatively simple problem. I've plotted a 
series of contourf and contour plots on the same axes.
First I plot a contourf.
Next a contour on top of it.
Then I want a contourf plotted on top of both the previous contourf and 
contour plots.
And finally, a contour on top of the second contourf.
However, when I do this the result is the two contour plots are drawn on 
top of the contourf plots no matter what. How do I hide the contours 
under a contourf?
Jordan