plscolbg: Set the background color
by 8-bit RGB value 

DESCRIPTION:

    Set the background color (color 0 in color map 0) by 8-bit RGB value
    (see
    the PLplot documentation). 

SYNOPSIS:

plscolbg(r, g, b)

ARGUMENTS:

    r (PLINT, input) :      Unsigned 8-bit integer (0-255) representing the
    degree of red in the color. 

    g (PLINT, input) :      Unsigned 8-bit integer (0-255) representing the
    degree of green in the color. 

    b (PLINT, input) :      Unsigned 8-bit integer (0-255) representing the
    degree of blue in the color.