Colors in overlay graphs

[PTD_SAS]

I use Gplot to overlay 18-20 graphs in the same screen and would like different colors for each of them.

For the symbol statement I use repeat=20 without specifying colors,so the charts are created but the colors are repeated after the 12th graph, seems like the automatically selected colors are only 12, the 13th one is the same as the 1st.

What can I do to force SAS to automatically select different colors for each of the 20 graphs?

[Ksharp]

It is SAS/Graph question. Post is at SAS/GRAPH and ODS Graphics 

Robert.Allison is good at it . Here is his website.

http://robslink.com 

[ballardw]

Old school solution:

Define 20 symbol statements SYMBOL1 to SYMBOL20, each with the color you want.

The plot statement would be

plot y*x1=1 y*x2=2 y*x3=3 ... y*x20=20 / <options>;

The recycle at 12 is I believe a sideffect of ODS Styles as they predefine 12 data colors.