I don't think it makes sense. The index is a discrete variable, but derivatives only make sense for continuous variables.
Aaron Meurer On Thu, Jan 26, 2017 at 1:06 PM, Francesco Bonazzi <[email protected]> wrote: > This could solve the issue https://github.com/sympy/sympy/issues/11444 > > Expr.is_constant() checks whether the expression derivative by its free > symbols is nonzero. Unfortunately A[i].diff(i) currently gives 0. > > Free symbols of A[i] are A and i. > > > On Thursday, 26 January 2017 17:04:01 UTC+1, Björn Dahlgren wrote: >> >> >> Do you have an applied example where this would help? If it simplifies >> users' code I think that would be an argument for it. > > > Not really, indices are supposed to be integers, the derivative doesn't > make any sense. On the other hand integer symbols are still derivable in > SymPy. > > Furthermore, nothing forbids to use indexed objects as very strange > functions. > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/sympy. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sympy/b3729b12-0fbd-4fa2-ab6a-c944fef19f11%40googlegroups.com. > > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAKgW%3D6%2BCZk6DHPROFoj0959xwmJaT540h38%3DAnPhCoc6Q7bP%3DQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
