Another couple of tweaks to the PS driver to fix bugs. The code included some instances of the
string "\\" which were assumed to be interpreted by the compiler as "\". This doesn't work on all compilers so replaced this with char(92). Also, the prolog was being written with two instances of "%% Orientation", one specifying Landscape and the other Portrait. This was confusing Illustrator on the Mac.
Keywords: HEAsoft, pgplot