How can I extract random data from a matrix?

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Hi everyone.
I have a M rows by N columns matrix and I need to extract X random samples of it of the same size. I suposse is a simple task but I'm new at Matlab.
Thanks a lot.

Risposta accettata

Azzi Abdelmalek
Azzi Abdelmalek il 14 Set 2012
Modificato: Azzi Abdelmalek il 14 Set 2012
A=rand(10,5) %your matrix aray
B=A(:)
X=20; %number of random sample
[v,idx]=sort(rand(1,numel(A)));
Samples=B(idx(1:X))
  2 Commenti
Gerardo
Gerardo il 16 Set 2012
Thanks for your help Azzi, it works great.
Azzi Abdelmalek
Azzi Abdelmalek il 16 Set 2012
using Sean Wolski suggestion (randperm)
A=rand(10,5) %your matrix aray
Samples=A(randperm(numel(A),20))

Accedi per commentare.

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Sean de Wolski
Sean de Wolski il 14 Set 2012
doc randperm

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