Re: How to make a loop for this problem!

*To*: mathgroup at smc.vnet.net*Subject*: [mg75371] Re: How to make a loop for this problem!*From*: dh <dh at metrohm.ch>*Date*: Fri, 27 Apr 2007 05:21:51 -0400 (EDT)*References*: <f0pkt5$28h$1@smc.vnet.net>

Hi, you want 512 3x3 binary matrices that are all different. Well, this exhausts just about all such matrices. We can therefore create them in an orderly way instead of randomly. Now, all 9 bits of one matrix can be thougth of as a binary number between 0 and 511. We therefore, first generate the numbers in decimal notation, convert them to 9 binary bits and assemble them in 3x3 matrices: d=IntegerDigits[Range[0,511],2,9] ; d=Partition[#,3]&/@ d ; this gives an ordered list of all possible such matrices. hope this helps, Daniel pskmaths at googlemail.com wrote: > Hi all, > > This comand: > A = Array[Random[Integer] &, {3, 3}] > generates a 3x3 random matrix its terms between 0 and 1. > > I need to make a loop that geerates a finite number of matrices, let's > say 512 and this loop check that non of the matrices is equal to > another one (no repeated matrices) > > I can geerate thoses random, matrices with this command: > Do[Print[Array[Random[Integer] &, {3, 3}]], {512}] > but I may have two matrices that are equal and also as far as I know I > cann't use the out put because of the command, Print. > >