Hello,
I found that Maxima has trouble solving some very simple ode's, e.g.,
(%i1) ode2('diff(y,t,2)+'diff(y,t)+y-sin(t),y,t);
After a few minutes of churning maxima leaves the following message:
!!! CMUCL has run out of dynamic heap space. You can control heap size
!!! with the -dynamic-space-size commandline option.
*A2 gc_alloc_new_region failed, nbytes=16.
Generation Boxed Unboxed LB LUB Alloc Waste Trig WP GCs
Mem-age
0: 1645 0 0 0 6734384 3536 2000000 0 0
0.0000
1: 5480 1 0 0 22431040 19136 2000000 5479 0
0.0000
2: 22108 1 0 0 90504704 53760 2000000 22107 0
0.0000
3: 101833 4 0 0 416906528 217824 2000000 101824
0 0.0000
4: 0 0 0 0 0 0 2000000 0 0
0.0000
5: 0 0 0 0 0 0 2000000 0 0
0.0000
6: 0 0 0 0 0 0 0 0 0
0.0000
Total bytes alloc=536576656
I am running Mandrake 10.0 with the 2.6.3 kernel and Maxima 5.9.1
compiled with cmucl 18e.
If the ode is changed slightly or if Maxima is told to solve
the complexified equation, then Maxima responds with the
solution instantly. eg,
(%i1) ode2('diff(y,t,2)+'diff(y,t)+2*y-sin(t),y,t);
(%i2) realpart(second(ode2('diff(y,t,2)+'diff(y,t)+y-exp(%i*t),y,t)));
Am I doing something to cause this behavior or is this a bug in ode2?
Sincerely,
Moses