7.15 black in color structures (24.10.01)

7.15.1 Dr. U. Kasper

I have some PLOT (not plot) structures with different COLORs and I am unable to give one of them the color black. What are the values (or the value) for RGB, HUE or HSV? Or is there an other option for this?

7.15.2 Theodore Kolokolnikov (25.10.01)

The trick I use is the following. Suppose that ’pic’ is your plot structure, for example:

pic := plot(sin(x),x=0..10):
 

Then you can do this:

eval(subs(COLOUR=(()->NULL), pic));
 

This will turn everything in your picture black.

7.15.3 Robert Israel (25.10.01)

Black isCOLOUR(RGB,0,0,0). It doesn’t have a HUE. In HSV it would be COLOUR(HSV,h,s,0) where h and s can be anything from 0 to 1.

You can get the RGB values for the named colours from the table `plot/colortable`. So, for example:

> `plot/colortable`[sienna]; 
 
    [.55686275, .41960784, .13725490]