Thread: [Matplotlib-users] Trouble with colorbar cspacing='linear'

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Hello, 
 
I am trying to construct a contour plot where the contours are
separated by a constant amount but I would like a color bar (or
something) to show what the values of the different levels are. I will
have too many contours for clabels to be effective. 
 
When I use colorbar with unequally spaced contours and use
cspacing='linear' the ticks are spaced nicely but the colors are not. 
 
The following code exemplifies the problem: 
 
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<pre>#!/usr/bin/python
from pylab import *

<span style="color: rgb(128, 128, 128);"><i>#Compute Data</i></span>
delta <span
 style="color: rgb(255, 0, 255);">=</span> <span
 style="color: rgb(128, 0, 128);">0.025</span>
x <span
 style="color: rgb(255, 0, 255);">=</span> arange<span
 style="color: rgb(255, 0, 255);">(-</span><span
 style="color: rgb(128, 0, 128);">3.0</span>, <span
 style="color: rgb(128, 0, 128);">3.0</span>, delta<span
 style="color: rgb(255, 0, 255);">)</span>
y <span
 style="color: rgb(255, 0, 255);">=</span> arange<span
 style="color: rgb(255, 0, 255);">(-</span><span
 style="color: rgb(128, 0, 128);">2.0</span>, <span
 style="color: rgb(128, 0, 128);">2.0</span>, delta<span
 style="color: rgb(255, 0, 255);">)</span>
X, Y <span
 style="color: rgb(255, 0, 255);">=</span> meshgrid<span
 style="color: rgb(255, 0, 255);">(</span>x, y<span
 style="color: rgb(255, 0, 255);">)</span>
Z1 <span
 style="color: rgb(255, 0, 255);">=</span> bivariate_normal<span
 style="color: rgb(255, 0, 255);">(</span>X, Y, <span
 style="color: rgb(128, 0, 128);">1.0</span>, <span
 style="color: rgb(128, 0, 128);">1.0</span>, <span
 style="color: rgb(128, 0, 128);">0.0</span>, <span
 style="color: rgb(128, 0, 128);">0.0</span><span
 style="color: rgb(255, 0, 255);">)</span>
Z2 <span
 style="color: rgb(255, 0, 255);">=</span> bivariate_normal<span
 style="color: rgb(255, 0, 255);">(</span>X, Y, <span
 style="color: rgb(128, 0, 128);">1.5</span>, <span
 style="color: rgb(128, 0, 128);">0.5</span>, <span
 style="color: rgb(0, 0, 255);">1</span>, <span
 style="color: rgb(0, 0, 255);">1</span><span
 style="color: rgb(255, 0, 255);">)</span>
<span style="color: rgb(128, 128, 128);"><i># difference of Gaussians</i></span>
Z <span
 style="color: rgb(255, 0, 255);">=</span> <span
 style="color: rgb(128, 0, 128);">100.0</span> <span
 style="color: rgb(255, 0, 255);">*</span> <span
 style="color: rgb(255, 0, 255);">(</span>Z2 <span
 style="color: rgb(255, 0, 255);">-</span> Z1<span
 style="color: rgb(255, 0, 255);">)</span>

<span style="color: rgb(128, 128, 128);"><i>#Draw figure</i></span>
figure<span
 style="color: rgb(255, 0, 255);">()</span>
levels<span
 style="color: rgb(255, 0, 255);">=[-</span><span
 style="color: rgb(0, 0, 255);">9</span>,<span
 style="color: rgb(255, 0, 255);">-</span><span
 style="color: rgb(128, 0, 128);">7.5</span>,<span
 style="color: rgb(255, 0, 255);">-</span><span
 style="color: rgb(0, 0, 255);">5</span>,<span
 style="color: rgb(255, 0, 255);">-</span><span
 style="color: rgb(128, 0, 128);">2.5</span>,<span
 style="color: rgb(255, 0, 255);">-</span><span
 style="color: rgb(128, 0, 128);">0.5</span>,<span
 style="color: rgb(128, 0, 128);">0.5</span>,<span
 style="color: rgb(128, 0, 128);">2.5</span>,<span
 style="color: rgb(0, 0, 255);">5</span>,<span
 style="color: rgb(128, 0, 128);">7.5</span>,<span
 style="color: rgb(0, 0, 255);">9</span><span
 style="color: rgb(255, 0, 255);">]</span>
CS <span
 style="color: rgb(255, 0, 255);">=</span> contour<span
 style="color: rgb(255, 0, 255);">(</span>Z, levels,
             origin<span
 style="color: rgb(255, 0, 255);">=</span><span
 style="color: rgb(221, 0, 0);">'lower'</span>,
             linewidths<span
 style="color: rgb(255, 0, 255);">=</span><span
 style="color: rgb(0, 0, 255);">2</span>,
             extent<span
 style="color: rgb(255, 0, 255);">=(-</span><span
 style="color: rgb(0, 0, 255);">3</span>,<span
 style="color: rgb(0, 0, 255);">3</span>,<span
 style="color: rgb(255, 0, 255);">-</span><span
 style="color: rgb(0, 0, 255);">2</span>,<span
 style="color: rgb(0, 0, 255);">2</span><span
 style="color: rgb(255, 0, 255);">))</span>
clabel<span
 style="color: rgb(255, 0, 255);">(</span>CS,
       inline<span
 style="color: rgb(255, 0, 255);">=</span><span
 style="color: rgb(0, 0, 255);">1</span>,
       fmt<span
 style="color: rgb(255, 0, 255);">=</span><span
 style="color: rgb(221, 0, 0);">'%1.1f'</span>,
       fontsize<span
 style="color: rgb(255, 0, 255);">=</span><span
 style="color: rgb(0, 0, 255);">14</span><span
 style="color: rgb(255, 0, 255);">)</span>

colorbar<span
 style="color: rgb(255, 0, 255);">(</span>CS,cspacing<span
 style="color: rgb(255, 0, 255);">=</span><span
 style="color: rgb(221, 0, 0);">'linear'</span><span
 style="color: rgb(255, 0, 255);">)</span>  <span
 style="color: rgb(128, 128, 128);"><i># make a colorbar for the contour lines</i></span>
title<span
 style="color: rgb(255, 0, 255);">(</span><span
 style="color: rgb(221, 0, 0);">"ColorBar lines don't match ticks"</span><span
 style="color: rgb(255, 0, 255);">)</span>
savefig<span
 style="color: rgb(255, 0, 255);">(</span><span
 style="color: rgb(221, 0, 0);">'BadColorBar'</span><span
 style="color: rgb(255, 0, 255);">)</span>
show<span
 style="color: rgb(255, 0, 255);">()</span>
</pre>
<br>
I have attached the file 'BadColorBar.png'<br>
<br>
Any help would be appreciated,<br>
Karl Edler<br>
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Thread: [Matplotlib-users] Trouble with colorbar cspacing='linear'

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