Re: Differences in Random Numbers

*To*: mathgroup at smc.vnet.net*Subject*: [mg46813] Re: Differences in Random Numbers*From*: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>*Date*: Tue, 9 Mar 2004 04:30:59 -0500 (EST)*Organization*: Universitaet Leipzig*References*: <c2hdhe$abi$1@smc.vnet.net>*Reply-to*: kuska at informatik.uni-leipzig.de*Sender*: owner-wri-mathgroup at wolfram.com

Mark Coleman wrote: > > Greetings, > > My understanding is that the built-in Mathematica command Random[ ] will > produce a uniformly distributed pseudo-random number in the range 0 to > 1. Based on my read of the documentation, this should be equivalent to > calling Random[UniformDistribution[0,1]] (after loading > Statistics`ContinuousDistributions of course)). Is this correct? The source code say UniformDistribution/: Random[UniformDistribution[min_:0, max_:1]] := Random[Real, {min, max}] > > I ask this question because of some unusual results I obtained while > testing another (fairly complex) program that makes use of uniform > random variates. I initially used the Random[UniformDistribution[0,1]] > function call and obtained final results of the complex program that > were quire a bit different from the test case that I have been using to > verify my code. When I switched to the simple Random[ ] call, my > results looked much better. Sorry if this seems vague, but I found this > behavior somewhat anomalous and wanted to be sure I understood the > differences, in any, between these two methods of generating random > variates. Just try it out SeedRandom[1234]; Table[Random[], {10}] and SeedRandom[1234]; Table[Random[UniformDistribution[0, 1]], {10}] will produce the same list. Regards Jens