python matplotlib: how to use fill_between with a colormap to fill the background of a 2d plot? -

i'm trying make simple 2d plot 3 column data sets e.g. y=f(x) , z=f(x). want plot xy , display z using color. example, rectangular regions between [x1,x2, min(y), max(y)] ... filled background color depending on value of z. tried use fill_between not associate colormap it. i'm new matplotlib , python. appreciate comments/suggestions.

edit: don't have accurate plot i'll try explain query of following figure sample plot

say between x=0.5 x=1, z=1 x=1.0, x=1.5, z=2 ....

so cover x=0.5 x=1 (min(y) max(y)] color corresponds z=1, , between x=1, x=1.5, z=2 , on.. want show variation using colormap , display colorbar @ right side.

it sound me should use contourf

http://matplotlib.org/examples/pylab_examples/contourf_demo.html

this take x dependant variable, produce y = y(x) , z = z(x). seems z not dependant on y contourf can still handle this.

as simple example:

import pylab plt x = plt.linspace(0,2,100) y = plt.linspace(0,10,100)  z = [[plt.sinc(i) in x] j in y]  cs = plt.contourf(x, y, z, 20, # \[-1, -0.1, 0, 0.1\],                         cmap=plt.cm.rainbow) plt.colorbar(cs) plt.plot(x,2+plt.sin(y), "--k") 

the many variations captures elements looking for