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antonv wrote:
> Thanks for the explanation Eric. Now it makes sense. As pcolor does not allow
> interpolation, my last chance is to use imshow but that creates another
> issue as it allows only one argument (z) not 3 (x,y,z) as pcolor or contourf
> and it will display the whole dataset instead of the zoomed area. Is there a
> way to have it display just a region?
Yes, just set the view limits, the same as for contourf or pcolor. You 
use the extent kwarg to effectively define the x and y grid, but that 
grid must be uniform and rectangular. See 
http://matplotlib.sourceforge.net/examples/pylab_examples/image_masked.html
> 
> Another way that I could be able to solve my issue is by overlapping the
> contourf ovet the pcolor graph. Is there a way to do that when I have the
> commands one after the other, the last one clears the previous?
Yes, with matplotlib you can plot just about anything on top of anything 
else--but why would you want to in this case? It doesn't make sense to 
me. What is wrong with your original contourf version? (It looks to me 
like there is something odd about the combination of color map and 
contour levels--are you using a normal color map with 256 values? And, 
it looks like maybe you want something other than the lowest colormap 
value for the no-data regions; the image_masked example above shows how 
you can get that using the set_bad method of the colormap.)
Eric
> 
> Thanks,
> Anton
> 
> 
> 
> efiring wrote:
>> antonv wrote:
>>> Ok. Then what do you think would be the best way to have a smooth graph
>>> like
>>> the contourf but with the data shown by pcolor? The best of both worlds
>>> in
>>> other words :)
>>>
>>> Thanks,
>>> Anton
>> Anton,
>>
>> The other thing to bear in mind is that with contourf, you are 
>> specifying the data values at grid points, and the algorithm is 
>> essentially interpolating to calculate the boundaries of polygons for 
>> which the data are between two adjacent contour levels; with pcolor you 
>> are specifying the boundaries of a grid, and your data values determine 
>> the colors of those rectangles (or more generally, quadrilaterals). 
>> That is, with pcolor your data value, Zij, determines the color of the 
>> box with corners at Xij,Yij and Xi+1 j+1, Yi+1 j+1.
>>
>> Eric
>>
>>>
>>>
>>> Jeff Whitaker wrote:
>>>> antonv wrote:
>>>>> When plotting the same ocean data with contourf or pcolor I noticed a
>>>>> difference at the edge between ocean area and the land where there is
>>>>> no
>>>>> data. Basically, contourf is trimming from the edge and when using
>>>>> basemap
>>>>> you can see the underlying fill color. Is this normal behaviour or am I
>>>>> doing something wrong?
>>>>>
>>>>> I've attached 2 images to show exactly what is happening.
>>>>>
>>>>> Thanks,
>>>>> Anton
>>>>>
>>>>>
>>>>> http://www.nabble.com/file/p21397184/img_contourf.png img_contourf.png 
>>>>> http://www.nabble.com/file/p21397184/img_pcolor.png img_pcolor.png 
>>>>> 
>>>> Anton: Contourf and pcolor deal with missing values in masked arrays 
>>>> differently, so yes - I think this is normal behavior.
>>>>
>>>> -Jeff
>>>>
>>>> ------------------------------------------------------------------------------
>>>> Check out the new SourceForge.net Marketplace.
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>>
>>
> 

Thanks for the explanation Eric. Now it makes sense. As pcolor does not allow
interpolation, my last chance is to use imshow but that creates another
issue as it allows only one argument (z) not 3 (x,y,z) as pcolor or contourf
and it will display the whole dataset instead of the zoomed area. Is there a
way to have it display just a region?
Another way that I could be able to solve my issue is by overlapping the
contourf ovet the pcolor graph. Is there a way to do that when I have the
commands one after the other, the last one clears the previous?
Thanks,
Anton
efiring wrote:
> 
> antonv wrote:
>> Ok. Then what do you think would be the best way to have a smooth graph
>> like
>> the contourf but with the data shown by pcolor? The best of both worlds
>> in
>> other words :)
>> 
>> Thanks,
>> Anton
> 
> Anton,
> 
> The other thing to bear in mind is that with contourf, you are 
> specifying the data values at grid points, and the algorithm is 
> essentially interpolating to calculate the boundaries of polygons for 
> which the data are between two adjacent contour levels; with pcolor you 
> are specifying the boundaries of a grid, and your data values determine 
> the colors of those rectangles (or more generally, quadrilaterals). 
> That is, with pcolor your data value, Zij, determines the color of the 
> box with corners at Xij,Yij and Xi+1 j+1, Yi+1 j+1.
> 
> Eric
> 
>> 
>> 
>> 
>> Jeff Whitaker wrote:
>>> antonv wrote:
>>>> When plotting the same ocean data with contourf or pcolor I noticed a
>>>> difference at the edge between ocean area and the land where there is
>>>> no
>>>> data. Basically, contourf is trimming from the edge and when using
>>>> basemap
>>>> you can see the underlying fill color. Is this normal behaviour or am I
>>>> doing something wrong?
>>>>
>>>> I've attached 2 images to show exactly what is happening.
>>>>
>>>> Thanks,
>>>> Anton
>>>>
>>>>
>>>> http://www.nabble.com/file/p21397184/img_contourf.png img_contourf.png 
>>>> http://www.nabble.com/file/p21397184/img_pcolor.png img_pcolor.png 
>>>> 
>>> Anton: Contourf and pcolor deal with missing values in masked arrays 
>>> differently, so yes - I think this is normal behavior.
>>>
>>> -Jeff
>>>
>>> ------------------------------------------------------------------------------
>>> Check out the new SourceForge.net Marketplace.
>>> It is the best place to buy or sell services for
>>> just about anything Open Source.
>>> http://p.sf.net/sfu/Xq1LFB
>>> _______________________________________________
>>> Matplotlib-users mailing list
>>> Mat...@li...
>>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>>>
>>>
>> 
> 
> 
> ------------------------------------------------------------------------------
> Check out the new SourceForge.net Marketplace.
> It is the best place to buy or sell services for
> just about anything Open Source.
> http://p.sf.net/sfu/Xq1LFB
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> 
> 
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antonv wrote:
> Ok. Then what do you think would be the best way to have a smooth graph like
> the contourf but with the data shown by pcolor? The best of both worlds in
> other words :)
> 
> Thanks,
> Anton
Anton,
The other thing to bear in mind is that with contourf, you are 
specifying the data values at grid points, and the algorithm is 
essentially interpolating to calculate the boundaries of polygons for 
which the data are between two adjacent contour levels; with pcolor you 
are specifying the boundaries of a grid, and your data values determine 
the colors of those rectangles (or more generally, quadrilaterals). 
That is, with pcolor your data value, Zij, determines the color of the 
box with corners at Xij,Yij and Xi+1 j+1, Yi+1 j+1.
Eric
> 
> 
> 
> Jeff Whitaker wrote:
>> antonv wrote:
>>> When plotting the same ocean data with contourf or pcolor I noticed a
>>> difference at the edge between ocean area and the land where there is no
>>> data. Basically, contourf is trimming from the edge and when using
>>> basemap
>>> you can see the underlying fill color. Is this normal behaviour or am I
>>> doing something wrong?
>>>
>>> I've attached 2 images to show exactly what is happening.
>>>
>>> Thanks,
>>> Anton
>>>
>>>
>>> http://www.nabble.com/file/p21397184/img_contourf.png img_contourf.png 
>>> http://www.nabble.com/file/p21397184/img_pcolor.png img_pcolor.png 
>>> 
>> Anton: Contourf and pcolor deal with missing values in masked arrays 
>> differently, so yes - I think this is normal behavior.
>>
>> -Jeff
>>
>> ------------------------------------------------------------------------------
>> Check out the new SourceForge.net Marketplace.
>> It is the best place to buy or sell services for
>> just about anything Open Source.
>> http://p.sf.net/sfu/Xq1LFB
>> _______________________________________________
>> Matplotlib-users mailing list
>> Mat...@li...
>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>>
>>
> 

El dom, 11-01-2009 a las 16:48 +0100, Goyo escribió:
> El jue, 08-01-2009 a las 12:09 -0600, de...@ve... escribió:
> > I am sure this is a well know issue, so please feel free to just give a 
> > link if the answer and solution are long. I have a newly installed 
> > matplotlib installations running on Windows XP using Python 2.5.4. When 
> > I execute a simple 4 line example (copied directly from the PyPlot 
> > tutorial) in either PythonWin or IDLE, , it works fine and I terminate 
> > by right clicking on the generated figure and doing a Close. However, 
> > when I rerun the code from the IDE (makes no difference if I use 
> > PythonWin or IDLE) the figure hangs and eventually I get an abnormal 
> > exit and crash out of the IDE (in PythonWin there is a dialogue box that 
> > says "Runtime Error" in pythonwin.exe. This makes debugging in an IDE 
> > very clumsy, because I need to exit and restart it every time I run 
> > python code.
> > 
> > The test code is simply:
> > 
> > import matplotlib.pyplot as plt
> > plt.plot([1,2,3])
> > plt.ylabel('Some Numbers')
> > plt.show()
> > 
> > 
> > Thanks in advance,
> > 
> > David Lees
> 
> Interactive mode works for me in an IDLE shell:
> 
> import matplotlib.pyplot as plt
> plt.ion()
> plt.plot([1,2,3])
> plt.ylabel('Some Numbers')
> plt.show() # You don't have to call show() in interactive mode though
> 
> Goyo
I'm using the TKAgg backend, I guess there will be problems with other
interactive backends.
Goyo

El jue, 08-01-2009 a las 12:09 -0600, de...@ve... escribió:
> I am sure this is a well know issue, so please feel free to just give a 
> link if the answer and solution are long. I have a newly installed 
> matplotlib installations running on Windows XP using Python 2.5.4. When 
> I execute a simple 4 line example (copied directly from the PyPlot 
> tutorial) in either PythonWin or IDLE, , it works fine and I terminate 
> by right clicking on the generated figure and doing a Close. However, 
> when I rerun the code from the IDE (makes no difference if I use 
> PythonWin or IDLE) the figure hangs and eventually I get an abnormal 
> exit and crash out of the IDE (in PythonWin there is a dialogue box that 
> says "Runtime Error" in pythonwin.exe. This makes debugging in an IDE 
> very clumsy, because I need to exit and restart it every time I run 
> python code.
> 
> The test code is simply:
> 
> import matplotlib.pyplot as plt
> plt.plot([1,2,3])
> plt.ylabel('Some Numbers')
> plt.show()
> 
> 
> Thanks in advance,
> 
> David Lees
Interactive mode works for me in an IDLE shell:
import matplotlib.pyplot as plt
plt.ion()
plt.plot([1,2,3])
plt.ylabel('Some Numbers')
plt.show() # You don't have to call show() in interactive mode though
Goyo

Ok. Then what do you think would be the best way to have a smooth graph like
the contourf but with the data shown by pcolor? The best of both worlds in
other words :)
Thanks,
Anton
Jeff Whitaker wrote:
> 
> antonv wrote:
>> When plotting the same ocean data with contourf or pcolor I noticed a
>> difference at the edge between ocean area and the land where there is no
>> data. Basically, contourf is trimming from the edge and when using
>> basemap
>> you can see the underlying fill color. Is this normal behaviour or am I
>> doing something wrong?
>>
>> I've attached 2 images to show exactly what is happening.
>>
>> Thanks,
>> Anton
>>
>>
>> http://www.nabble.com/file/p21397184/img_contourf.png img_contourf.png 
>> http://www.nabble.com/file/p21397184/img_pcolor.png img_pcolor.png 
>> 
> Anton: Contourf and pcolor deal with missing values in masked arrays 
> differently, so yes - I think this is normal behavior.
> 
> -Jeff
> 
> ------------------------------------------------------------------------------
> Check out the new SourceForge.net Marketplace.
> It is the best place to buy or sell services for
> just about anything Open Source.
> http://p.sf.net/sfu/Xq1LFB
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
> 
> 
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antonv wrote:
> When plotting the same ocean data with contourf or pcolor I noticed a
> difference at the edge between ocean area and the land where there is no
> data. Basically, contourf is trimming from the edge and when using basemap
> you can see the underlying fill color. Is this normal behaviour or am I
> doing something wrong?
>
> I've attached 2 images to show exactly what is happening.
>
> Thanks,
> Anton
>
>
> http://www.nabble.com/file/p21397184/img_contourf.png img_contourf.png 
> http://www.nabble.com/file/p21397184/img_pcolor.png img_pcolor.png 
> 
Anton: Contourf and pcolor deal with missing values in masked arrays 
differently, so yes - I think this is normal behavior.
-Jeff

David Trethewey wrote:
> How do you install the high and full resolution coastline datasets? I've 
> tried simply downloading them from the internet from 
> http://www.soest.hawaii.edu/wessel/gshhs/gshhs.html and copying them 
> into the basemap data directory but this didn't work.
>
> David
>
> 
David: The high and full resolution datasets are included in the basemap 
distribution (available at http://sf.net/projects/matplotlib). I 
presume you are using Basemap from Enthough Python (which excluded those 
datasets, presumably to save space). If so, just install Basemap again 
from the sourceforge download and you will get them.
-Jeff

How do you install the high and full resolution coastline datasets? I've 
tried simply downloading them from the internet from 
http://www.soest.hawaii.edu/wessel/gshhs/gshhs.html and copying them 
into the basemap data directory but this didn't work.
David

When plotting the same ocean data with contourf or pcolor I noticed a
difference at the edge between ocean area and the land where there is no
data. Basically, contourf is trimming from the edge and when using basemap
you can see the underlying fill color. Is this normal behaviour or am I
doing something wrong?
I've attached 2 images to show exactly what is happening.
Thanks,
Anton
http://www.nabble.com/file/p21397184/img_contourf.png img_contourf.png 
http://www.nabble.com/file/p21397184/img_pcolor.png img_pcolor.png 
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What is the simple way to do the following?
I want to set the size of the actual axes box
(i.e, , the lines drawn for the axes, not
including the ticks and labels.)
I do not care about the figure size, but I
would like the resulting drawing to have
a tight bounding box. (After I add the
ticks and axes labels.)
The best I've come up with so far is to
create a figure with a set size, and then
add axes with a specified rectangle.
But this does not give a neat path to
what I want.
Thanks,
Alan Isaac