[sage-devel] Re: Something.expand() is 0 but factor() is not zero

I meant to say that f.expand() gives the correct answer. To see why, factor out the common factors (x-y)(y-z)(z-x). Once you did so, the rest is ( (x-y) + (y-z) + (z-x) ) and so I expect f.factor() returns 0. The statement "the given expression cannot be factorized further" seems weird to me. --

[sage-devel] Something.expand() is 0 but factor() is not zero

The following code > var("z y z") > f = (x-y)^2*(y-z)*(z-x) + (y-z)^2*(z-x)*(x-y) + (z-x)^2*(x-y)*(y-z) > f.expand() outputs 0. But > f.factor() simply prints the original formula (x-y)^2... Maybe something is wrong? -- You received this message because you are subscribed to the Google Groups

[sage-devel] arctanh vs. artanh

Hi all, Sage has built-in inverses of hyperbolic functions arcsinh, arccosh, arctanh, arccoth, arcsech, arccsch. But according to wikipedia , the initial should be ar- that stands for area. Perhaps for educational purpose we should use

[sage-devel] is_invertible() too slow comparing to rank() over GF(2^k)

I am running Sagemath 9.1 on macOS 10.15.17 but I think this issue is more about math. Consider the following code G = GL(2^8, GF(2^8)) A = G.random_element() B = Matrix(A) %time B.is_invertible() C = Matrix(A) %time C.nrows() == C.ncols() == C.rank() The first timer returns 9s while the second