用纯色填充轮廓部分

Question

I have a contour plot with some z values equal to zero. I want to shade all these values a particular color, from this

to this (MS Paint mock-up).

How can I go about doing so? Is there some feature in the library that will allow me to do this?

Answer 1

Have a look at the matplotlib contourplot and colormap demos. From the contour plot demo's last example, you can specify a colour map for the contour plot as follows

plt.figure()
# plots a bunch of colours
im = plt.imshow(Z, interpolation='bilinear', origin='lower',
                cmap=cm.gray, extent=(-3, 3, -2, 2))

# plot the contour lines 
levels = np.arange(-1.2, 1.6, 0.2)
CS = plt.contour(Z, levels,
                 origin='lower',
                 linewidths=2,
                 extent=(-3, 3, -2, 2))

you'll need to define your own color map if you want to leave some regions white/unfilled. The colormap is just a dict that maps numeric values to colours

https://matplotlib.org/examples/pylab_examples/contour_demo.html

https://matplotlib.org/examples/pylab_examples/custom_cmap.html