Thanks for pointing out sympy, I hadn't heard of it. I'm not sure why you're being sarcastic, I basically write python code full time. I'm quite familar with it, so I felt qualified to comment without doing any 'investigation'. I use ipython with the normal numpy/matplotlib/scipy numerical approach. You knew something I didn't, congratulations.
It qualifies me to talk about the python ecosystem, which I know quite well. I said something I thought was true, but wasn't. That's an honest mistake. I was unaware of a library, maybe even one that is well known. I was quite surprised I had missed something, and I said 'thanks for pointing that out'. I imagine it was a blind spot for me, as I always reach for Mathematica for symbolic work, so it just wasn't something I noticed.
I would never say things about ruby libraries, for example, as I don't know anything about it. I might say the same thing about R or matlab, which I do.
In the immortal words of pg:
When disagreeing, please reply to the argument instead of calling names.
E.g. "That is an idiotic thing to say; 1 + 1 is 2, not 3"
can be shortened to "1 + 1 is 2, not 3."
As in, 'python actually can do symbolic computation, see http://sympy.org'
I'm not blaming you for being wrong. I just don't think that having a good idea about the python ecosystem qualifies denying that you can do symbolic calculus, more than knowing how to sail qualifies you to say that the earth is flat.
Sorry I just thought it was impossible to not know about the whole python math stack being an actual ipython user, so assumed you were just paying lip service.
I love the amount of investigation people put into this sort of thing before making blanket statements like this.
Try it for yourself: http://live.sympy.org/I am no sympy expert at all - I figured it all out in the time since I read your comment. But of course I'm sure you love ipython as well.
(edit - fixed copy&pasting stupidness)