Maxima 5.9.0.1cvs Testing on Windows - GNUPLOT

PS.  To make gnuplot work I had to explicitly set the path in 
"mgnuplot.tcl" (having the exe in the path would probably work too - 
haven't tried this as out of time). 

The exe has to be "pgnuplot" which allows piping of commands under 
Windows.  I used version 3.8i which includes pgnuplot which in turn 
calls wgnuplot with redirected stdio.

The other modifications to "mgnuplot.tcl" are as follows:

#    exec rm -f $tmp
    file delete $tmp

and

#    while {[file exists $tmp] <= 0} {exec sleep 0}
    while {[file exists $tmp] <= 0} {}

which simply remove non-portable Unixisms.

Then

   plot3d(2^(x^2-y^2),[x,-1,1],[y,-2,2],[plot_format,gnuplot]);

does what it should (quite nicely too).

Cheers

Mike Thomas