How can I make a country plot in Sage/Maxima?

Question

I heard today that Maxima can do the country plot by contour_plot in Sage. I tried the following unsuccessfully to import Maxima:

from Maxima import contour_plot

I would like to make a similar map as here.

Answer 1

You probably mean a contour plot. Get a quick start and paste this code to your Sage Notobook:

f = lambda x,y: cos(x*y)

contour_plot(f, (-100, 4), (-4, 4))

More examples:

• http://www.flickr.com/photos/sagescreenshots/2131281877/
• http://norsemathology.org/wiki/index.php?title=Benchmarks