On Friday, April 10, 2020 at 8:48:26 PM UTC+2, Aaron Meurer wrote: > > On Fri, Apr 10, 2020 at 12:39 PM jlh <j...@gmx.ch <javascript:>> wrote: > > Technically even A ** 0 makes sense, which would just return > Identity(A.rows) (and funnily return a matrix of a different shape than the > power's base). > > Why rows and not columns though? I think A**0 should give an error. >
Actually it should be GenericIdentity(), which is also what is returned from MatMul() (with no arguments), which is pretty much equivalent to A ** 0. I don't think it should be an error, it's really the same as n ** 0 being 1. > Well I wouldn't be surprised if it breaks something somewhere if A**1 > stops working, since something might assume that A**1 is always the > same as A. I guess you can try removing it and seeing what tests fail. > But to me, mathematically, A**1 does make sense, even if none of the > other powers do. > I tried it, it didn't break any tests other than the ones in test_matpow.py explicitly testing for that. -- 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 sympy+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/aeb6c4be-b66e-4f55-961d-b62d8c58939b%40googlegroups.com.
