In Sage 5.4 determinant for dense matrix is very slow. For the following Hankel determinant calculation, Sage 4.6.1 is 100000 time more fast than Sage 5.4 (!!):
Sage 5.4, Sparse = False, Time=117.49 Sage 4.6.1, Sparse=False, Time=0.0011 # -------------------- import time def test(K, SP): n=100 f=taylor(prod((1-x**i) for i in range(1,n)),x,0,n) A=[f.coefficient(x,i) for i in range(n)] cf= [[A[i+j] for i in range(K)] for j in range(K)] m= matrix(ZZ, cf, sparse=SP) # t0=time.time() print " K =", K, ", result =", m.det() t_det= time.time()-t0 print " ",version() print " sparse= ", SP print " time = ", t_det KK=30 test(KK, True) print test(KK, False) # -------------------- -- You received this message because you are subscribed to the Google Groups "sage-support" group. To post to this group, send email to sage-support@googlegroups.com. To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support?hl=en.
