The arguments should contain respectively the x-coordinate, the lower y of the band for this x and the higher y bound of the band for this x.
The minimum permissible length of the vectors is 2, the maximum depends on the compilation parameter MXLIST (usually set either to 200 or to 1000 depending on the Patchy flag LONGLIST) and is equal to (MXLIST-1)/2.
The vectors should be 1-dimensional; matrices with another number of dimensions are unfolded before use.
This procedure does not accept scalar arguments.
Filling the area with yellow, gives good results when the plot is included in a black and white PostScript document: the area then appears as light grey.
Formatted on 21/01/18 at 16:55.