Maxima hangs, if the expression to plot with Draw2D or Draw3D contains units.
The only recover from such situation is
-
deactivate the command (otherwise the same happens upon reloading)
-
close the SMath program,
-
kill the maxima process in the program manager and
-
re-open the file and try to get rid of the units.
This is a very cumbersome procedure for a very common problem. Also, there is not always a chance to get rid of the units, due to simplification problems of SMath.
Suggested Mitigation:
Within the functions Draw2D or Draw3D, replace any unit by 1. This is safe, because in any case, the preprocessing replaces the units by base units. This may change in the future, but for now it is safe.
This might be done using local maxima definitions or by string replacment.
