DADiSP Worksheet Functions > Function Categories > Colors > RAINBOW

 

RAINBOW

Purpose:

Generates a colormap of the visible color spectrum.

Syntax:

RAINBOW(len)

len

-

Optional. An integer, the colormap length. Defaults to the length of the current colormap.

Returns:

A table of RGB triples suitable for the SETCOLORMAP function.

Example:

clen = length(getcolormap());

density(ravel(rep(0..(clen-1), 32), clen)');

rainbow;

 

image\rainbowpic.gif

 

creates a table of 32 x N (where N == colormap length) RBG values and displays the resulting colors. The resulting image is a vertical plot of colors ranging from blue (lowest) to red (highest).

Remarks:

rainbow by itself sets the colormap and shading.

 

a = rainbow or setcolormap(rainbow) returns the RGB values. In this case, use SETSHADING to make the new colormap take effect on an existing density or 2D plot.

See Also:

COOL

HOT

PINK

SETCOLORMAP

SETSHADING

SHOWCMAP