[pstricks] computing coordinates

[Juergen Gilg]

Dear Ziggy,

  I know that
\multido{\rx=0.0+0.2}{11}{\psline(\rx,-\rx)(2+\rx,-\rx)}
doesn't work, because postscript gets confused by "2+\rx".


try:

\multido{\rx=0.0+0.2}{11}{\psline(!\rx\space \rx\space neg)(!\rx\space 2 
add \rx\space neg)}

This should do the wanted. With the "!" you tell PSTricks to use the PS 
notation. PS notation doesn't have a "+" -- you use "add" instead in 
Reverse Polish Notation.

Hope this helps!

Regards,

Jürgen