2017-01-25 18:21:10 -0500 received badge ● Nice Question (source) 2017-01-25 13:57:29 -0500 received badge ● Student (source) 2017-01-25 13:51:40 -0500 asked a question Color parametric_plot3d by a rgb color rather than a colormap. I know I can color a 3d plot using a function and a color map. What I would like to do is to color a plot using a function that return a rgb color directly. Specifically, I am trying to plot complex functions on the Riemann sphere. I can show the argument using the HSV color map (which is incorrectly named since it only shows hue, not saturation nor value): sproj(x,y,z) = (x + I*y)/(1-z) cf = lambda u,v: N(arg(-f(sproj(cos(u)*cos(v),sin(u)*cos(v),sin(v))))/(2*pi)+0.5) cm = colormaps.hsv parametric_plot3d((cos(s)*cos(t),sin(s)*cos(t),sin(t)), (s,-pi,pi),(t,-pi/2,pi/2), color = (cf,cm))  This does not show the modulus, though. I would like to be able to do something like this: sproj(x,y,z) = (x + I*y)/(1-z) cf = lambda u,v: complex_to_rgb(-f(sproj(cos(u)*cos(v),sin(u)*cos(v),sin(v)))) parametric_plot3d((cos(s)*cos(t),sin(s)*cos(t),sin(t)), (s,-pi,pi),(t,-pi/2,pi/2), color = cf)