Hi everyone. I want to create a new matrix using a rand function and the values of other matrix.

I have a matrix (n,2) that have in the first column the min values and in the second column the max values. I want to create a new matrix (n,100) with uniform distributions in each row using the rand function and picking as MIN value the first value and as MAX value the second value from each row related to the matrix (n,2). In my code it always get the error "Size inputs must be scalar" in the the rand function.

Code:

p=length(t);
ii=1;
pdf=[];
while ii<=p
  IMIN=t(ii,1);
  IMAX=t(ii,2);
  pdf=rand([IMIN IMAX],p,100);
  ii=ii+1  
end

Answer 1

[dpb]

IMIN=t(:,1);
IMAX=t(:,2);
pdf=bsxfun(@plus,IMIN,bsxfun(@times,(IMAX-IMIN),rand(p,100)))

You can dispense with the intermediary IMIN/IMAX arrays in place of t, of course, used simply for legibility to aid in seeing the solution logic.

[João Narciso]

Thank you a lot!

Answer 2

[Kevin]

Are you thinking about generating uniformly distributed random integers? If yes, then you need to replace rand with randi in your code.

[dpb]

Good point -- if that's the case, the following may be more suitable--

pdf=cell2mat(arrayfun(@(imn,imx,p) randi([imn imx],1,p), ...
                  IMIN,IMAX,'uniformoutput',false));

will, however.