RE: random matrix initialisation...
- To: mathgroup at smc.vnet.net
- Subject: [mg37599] RE: [mg37576] random matrix initialisation...
- From: "David Park" <djmp at earthlink.net>
- Date: Wed, 6 Nov 2002 06:53:32 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Manuel,
matX[size_Integer?Positive, ones_Integer?NonNegative] /; ones <= size^2 :=
Partition[
RandomPermutation[Join[Array[1 &, ones], Array[0 &, size^2 - ones]]],
size]
matX[4, 3]
{{0, 0, 0, 0}, {0, 0, 1, 0}, {0, 0, 1, 0}, {0, 0, 1, 0}}
matX[4, 3]
{{0, 0, 0, 0}, {0, 0, 0, 0}, {0, 1, 1, 0}, {0, 0, 1, 0}}
David Park
djmp at earthlink.net
http://home.earthlink.net/~djmp/
From: Manuel Marques-Pita [mailto:manuxu at mac.com]
To: mathgroup at smc.vnet.net
hello,
i have a question regarding matrices. searched on the web and forums
but maybe due to using wrong keywords i am not finding an answer...
i need a way or function X to initialise matrices in mathematica such
that each time i call X i get a matrix with a predetermined number of
elements initialised as "1" and the rest as "0"
examples
X(4,3)
{{0,0,0,0}, {0,0,1,0}, {0,0,0,1}, {1,0,0,0}}
again X(4,3)
{{1,1,0,0}, {0,0,0,0}, {0,0,0,0}, {0,1,0,0}}
etc.. (first argument means that the matrix is 4x4 and second means
that there should be 3 "1's" present in the matrix
any help, pointers, etc will be appreciated!
thanks a lot
m
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