[pstricks] patch : autoscale y axis for psgraph

[Herbert Voss]

Martin Chicoine wrote:
> I changed lines 2047 and 2072 of the \psgraph definition in pstricks.tex 
> to :
> 
> \ifdim#6=0cm\pst at dima=\pst at tempA\pst at dimo\else\pst at dima=#6\fi\relax
> and
> \ifdim#8=0cm\pst at dima=\pst at tempA\pst at dimo\else\pst at dima=#8\fi\relax
> , respectively.
> 
> This allows to autoscale yLength (so that the scale of the x- and y-axis 
> are the same) if the user enters yLength=0cm.

Please give a full working minimal example, where
this maybe useful.

Thanks
Herbert