On Saturday, March 28, 2026 at 11:53:40 AM UTC+1 Georgi Guninski wrote: I believed that matrix multiplication and squaring to be significantly faster over GF(p) instead over ZZ.
Numerical evidence supports the opposite, is it a bug or reality? Session: def randmat(N,K): return Matrix(K,N,N,[K.random_element() for _ in range(N^2)]) N=200 Kq=GF(next_prime(2^200)) M1=randmat(N,Kq) %time MsZZ=M1.change_ring(ZZ)^2 #Wall time: 188 ms %time Msqu=M1^2 #Wall time: 7.75 s I would expect matrix multiplication to be around as fast over GF(p) and ZZ if the entries are the same. Large-p GF(p) matrices being a lot slower in Sage is surely because they use a generic matrix implementation rather than a specialized one. With current FLINT on my machine squaring a 200x200 matrix with 200-bit entries costs as follows: 0.032 seconds over ZZ with fmpz_mat 0.035 seconds over GF(p) with fmpz_mod_mat 0.029 seconds over GF(p) with mpn_mod_mat Fredrik -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/sage-devel/5bd108cd-ca0c-4b45-8193-dc1f51b010e2n%40googlegroups.com.
