The docstring of multiset_partitions describes how to count partitions. It mentions the nT function, but not where to get it. It's in sympy.functions.combinatorial.numbers
>>> from sympy.functions.combinatorial.numbers import nT >>> from sympy.utilities.iterables import multiset_partitions >>> len(list(multiset_partitions([1, 1, 2, 3], 3))) 4 >>> nT([1, 1, 2, 3], 3) 4 Also the docstring creates its own version of the Stirling numbers of the second kind, but there is a striling() function in the same module. So the documentation of multiset_partitions() could be improved. Also, some of these functions should probably be included in the default namespace (sympy/__init__.py). Aaron Meurer On Mon, Jun 17, 2019 at 2:40 PM Joan <[email protected]> wrote: > > I am using the multiset_partitions from sympy to get the possible > permutations of a list of elements, it does work wonderfully, but depending > on the case it will take a long time to generate the whole list. > Is there any way I can calculate the number of permutations prior generating > them? It would help to discard some complex calculations to be made. > > Thanks > > -- > 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/be1af050-ac6c-46a1-8107-e79a3d765feb%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%2Bg-EjmPP9%3DcwQwnsLxBRCtM2%2BE%3DybcOw9ADRHb6B%3DpNA%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
