So pypy is roughly 4.7x slower on this particular thing.
Do you have any plans to release pypy? I think it's getting very useful.
Ondrej
Yes, we have some plans to have a release at some point soon. There are no details though. Note that if you do this: from sympy import * var('x') from timeit import default_timer as clock t = clock(); a= sin(x).series(x, 0, 100); t = clock()-t; print t var('y') t = clock(); a= sin(y).series(y, 0, 100); t = clock()-t; print gap between pypy and cpython is getting smaller (some startup time is particularly large). I can do a bit profiling if you like. Regarding threaded - I think you should not assume that your argument is passed as keyword arg when using decorator I think. The other one looks like bug in pypy, but I'm not 100% sure. Cheers, fijal