On Mar 4, 3:13 pm, Mensanator <[EMAIL PROTECTED]> wrote: > On Mar 4, 12:32 pm, Nanjundi <[EMAIL PROTECTED]> wrote: > > > > Does seeding ( random.seed ) random with time fix this? It should. > > I suppose that depends on how long it takes factorint() to > process a number. If the seed is reset before the next clock > tick, you will get the same random numbers as the previous > iteration.
Alright, then make it constant and don't worry about the clock tick. >>> for i in xrange(10): ... f1 = random.choice(f) ... print f1, ... f2 = random.choice(f) ... print f2, ... C = f1*f2 ... ff = None ... ff = sympy.factorint(C) ... print ff ... random.seed(i) ... 5573 5171 [(5171, 1), (5573, 1)] 8537 7673 [(7673, 1), (8537, 1)] 2063 8573 [(2063, 1), (8573, 1)] 9551 9473 [(9473, 1), (9551, 1)] 2909 5659 [(2909, 1), (5659, 1)] 2897 1789 [(1789, 1), (2897, 1)] 6361 7541 [(6361, 1), (7541, 1)] 8017 8293 [(8017, 1), (8293, 1)] 3671 2207 [(2207, 1), (3671, 1)] 2803 9629 [(2803, 1), (9629, 1)] > Frankly, I don't understand why factorint() reseeds at all. Read the doc: * The rho algorithm is a Monte Carlo method whose outcome can be affected by changing the random seed value. * > Doesn't Random automatically initialize the seed? > Doesn't constantly reseeding degrade the performance of the > random number generator? With Robert Kern's patch, the reseeding > is no longer a constant, fixing the immediate symptom. Does it matter? The factorint reseeds using a constant seed (1234). > > But what if _I_ wanted to make a repeatable sequence for test > purposes? Wouldn't factorint() destroy my attempt by reseeding > on every call? Repeatable sequence? save it and reuse! Think about "What if"s doesn't get any work done. -N -- http://mail.python.org/mailman/listinfo/python-list
