Dear devs, Thanks a lot for a very nice and extremely useful python module. I recommend all my colleagues to try you package whenever they ask for a matlab like environment. This week one of these friends came by me with an oddity relating to the RandomArray module. try the following on your linux command prompt: while true; do python -c "from RandomArray import *;seed();print randint(100000)"; done and check the output. I get a steadily but slowly decreasing series of numbers. e.g: 4013 4013 4012 4012 4012 4012 4012 4012 4012 4012 4010 4010 4010 According to the documentation seed() should initiatilize from the system clock. If one checks the seed (using get_seed) it turns out to be the case indeed, but that it is only very slowly changing (once a second), and only on the second seed. e.g python -c "from RandomArray import *;seed();print get_seed()" (113161, 3079) (113161, 3079) (113161, 3080) (113161, 3080) (113161, 3080) (113161, 3080) My best guess is that this is the cause for the behavior seen above. This could be filed as a feature, but I believe it is not the behavior people would expect. At least the documentation should emphasize that two runs started within a short time ( upto 1s) will give the exact same result (experts on pseudo random numbers will know this, but the length of the time 1sec is surprisingly long). that the first random number is slowly varying (strongly correlated) with time (this is more surprising). One fix is to take one randomnumber and throw away, since the second number is not correlated with time (except from noted above). Best, Sune -- Software Application Manager Sune Rastad Bahn Phone: +45 35 320 638 Mobile: +45 23 455 997 Email: bahn@atomistix.com
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Sune Rastad Bahn