Re: The two dices
- To: mathgroup at smc.vnet.net
- Subject: [mg54492] Re: [mg54486] The two dices
- From: "Barthelet, Luc" <lucb at ea.com>
- Date: Tue, 22 Feb 2005 04:22:51 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
When you wrote dice[]+dice[] it became 2*dice[]. That's why you do not have odd numbers. By adding a parameter you prevented that simplification and you got the proper result. Luc http://www.mathematica-users.org -----Original Message----- From: Antoine [mailto:bugaboo12703 at yahoo.fr] To: mathgroup at smc.vnet.net Subject: [mg54492] [mg54486] The two dices Hello, I wanted to simulate the throws of two dices and something happened I can't explain: (Mathematica 5.0 , the same occurs on Mathematica 5.1 ) The following code is OK: n=300; theThrows = Table[Random[Integer, {1, 6}] + Random[Integer, {1, 6}], {n}]; theStats = Table[Count[theThrows, i], {i, 2, 12}] the occurences, as n becomes greater and greater, looks like the Gaussian curve (sorry for my English) Suppose you want your dice function, and that it is defined by dice[]:=Random[Integer, {1, 6}] ( nothing wrong about it, I suppose ) Now the behavior of the following code changes depending on the value of n. If n < 250 everything is fine ... hen n >= 250, then there is no occurence of odd values. ( the two dices never give 3, 5, ....) n=250; theThrows = Table[dice[] + dice[], {n}]; theStats = Table[Count[theThrows, i], {i, 2, 12}] Does a rationnal explanation exists ? Is it a bug ? The two definitions ( see below ) of the dice function "makes" the code running properly. But, of course, I prefer the former definition. dice:=Random[Integer, {1, 6}] ( not so nice, specially if you want to have several dice functions) dice[_]:=Random[Integer, {1, 6}] ( you must give a parameter to the function, quite horrible ) Thank you for your help. Antoine