[pstricks] Math expressions?

[Herbert Voss]

Johan Ekh schrieb:

> However, I plan to make extensive use of mathematical expressions in
> several kinds of
> drawing commands, not only \psarc. I try to reproduce a detailed
> structural drawing that
> requires that all the different parameters in the pstricks drawing
> commands are expressed
> with variables in mathematical expressions. For instance, in the \psarc
> case I would like
> to give the (x,y) pair and the radius, {r}, as expressions in addition
> to the angles.

(!x y) is mentioned in the docs ... (! ... any postscript code ...)
The radius is internally checked by another macro for a unit.
It is not possible without redefining of \psarc at ii to disable this
check.

HErbert