How to create a random data set from the possible values?
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    Tien Tran
 on 14 Apr 2016
  
    
    
    
    
    Commented: Walter Roberson
      
      
 on 14 Apr 2016
            I have eleven inputs, each input have several values. How can I create five hundred distinct sets of variables at random from the possible input values. (like following image)

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Accepted Answer
  Walter Roberson
      
      
 on 14 Apr 2016
        pops = {500:500:5000, .3:.05:.6, .5:.5:2.5, .5:.1:1, 200:100:500, 2:6, 4000:1000:8000, 100:100:1000, 2:1:8, 5:2.5:15, 30:10:70};
popL = cellfun(@length, pops(:).');
npop = length(pops);
N = 500;
popidx = floor(rand(N,npop) .* repmat(popL, N, 1))+1;
samps = cell2mat(arrayfun(@(IDX) pops{IDX}(popidx(:,IDX)).', 1:npop, 'Uniform', 0));
And now samps is a 500 x 11 array in which column K is uniformly randomly selected from pops{K}
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  Jos (10584)
      
      
 on 14 Apr 2016
				This is slightly easier:
camps = cell2mat(cellfun(@(c) reshape(c(randi(numel(c), N, 1)),N,1), pops, 'un', 0))
  Walter Roberson
      
      
 on 14 Apr 2016
				Yes, that is good too.
For whatever reason I figured it would be a good idea to calculate all of the indexes at the same time.
More Answers (1)
  Roger Stafford
      
      
 on 14 Apr 2016
        Let L be a column vector with eleven integers, each the count of the number of possible values in the corresponding set of the eleven sets.
   L = [10;7;5;6;4;5;5;10;7;5;5];  % The number of possibilities in each set
   I = ceil(L.*rand(11,1));  % I has random indices for each set
The vector I will then have random indices that can select one out of each of the sets of values you have listed.
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