[Matplotlib-users] Contour line data

[Mike H. <mh...@us...>]

How can I get the actual x,y data that represents the contour lines that 
are drawn with the contour() function?

I'd like to be able to redraw portions of those lines with different 
styles (dashed, dotted, etc.)

For example, given the following sample code (lifted from the sourceforge 
example):

from pylab import *
from numpy import *

delta = 0.025
x = arange(-3.0, 3.0, delta)
y = arange(-2.0, 2.0, delta)
X, Y = meshgrid(x, y)
Z1 = bivariate_normal(X, Y, 1.0, 1.0, 0.0, 0.0)
Z2 = bivariate_normal(X, Y, 1.5, 0.5, 1, 1)
# difference of Gaussians
Z = 10.0 * (Z2 - Z1)
figure()
cs = plt.contour(X, Y, Z)
show()

How could I, for example, re-draw the lines in the region X [0 1] Y [-1.5 
-0.5] as dashed?

I could do it, I think, if I had the for all the lines in the plot.

--Mike