Function: plotpointsize
Class: highlevel
Section: graphic
C-Name: rectpointsize
Prototype: vLG
Help: plotpointsize(w,size): change the "size" of following points in
 rectwindow w. w=-1 changes global value.
Doc: changes the ``size'' of following points in rectwindow $w$. If $w = -1$,
 change it in all rectwindows. This only works in the \kbd{gnuplot} interface.
