Plot3d seems to do something horrible with scaling.
Look at the following simple plot.
plot3d(x*y,[x,0,.1],[y,0,.1])
This gives a stepped plot, with only 10 distinct z values.
Along the same lines,
plot3d(x*y/1000,[x,0,1],[y,0,1]);
gives a plot with only *2* distinct z-values.
And for
plot3d(x*y,[x,0,.01],[y,0,.01])
and
plot3d(x*y/10000,[x,0,1],[y,0,1]);
I get division by zero.
Maxima version: 5.9.0
Maxima build date: 19:10 2/9/2003
host type: i686-pc-mingw32
lisp-implementation-type: Kyoto Common Lisp
lisp-implementation-version: GCL-2-5.0
Stavros Macrakis
2003-03-24
Logged In: YES
user_id=588346
A simpler error:
plot3d(1,[x,0,1],[y,0,1]) => Error: divide by zero (tcl)
Raymond Toy
2003-04-03
Logged In: YES
user_id=28849
Found the problem:
(defun print-pt1 (f str)
(format str "~,3f " f))
Thus, only 3 decimal places are printed.
Using either ~f or even ~,3g gives much better results.
Raymond Toy
2003-04-03
Raymond Toy
2003-04-03
Logged In: YES
user_id=28849
Applied the fix ",3g". Both examples plot just fine now.