On Mon, Jun 20, 2011 at 12:01 PM, Julien Rioux <[email protected]> wrote: > However, this is a new behavior compared to just a couple weeks ago (I > could not say when exactly was the last time I used git pull). The new > behavior assumes that the partial derivatives of the function f(x,y) > are continuous everywhere. See e.g. > http://en.wikipedia.org/wiki/Symmetry_of_second_derivatives#Non-symmetry > Is this change intended?
Yes, it is. See commit 53fbd255 [0] and issue 1435 [1]. We assume by default continuity of derivatives to the order needed, if the Derivatives are evaluated. It's planned to implement an assumption to allow the user to assume discontinuity of derivatives instead - issue 2471 [2]. Renato [0] https://github.com/sympy/sympy/commit/53fbd25510f0294d89398c5f9d0bee2f88492232 [1] http://code.google.com/p/sympy/issues/detail?id=1435 [2] http://code.google.com/p/sympy/issues/detail?id=2471 -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
