# Create a random Matrix

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Maurizio on 24 Oct 2011
I have a 8 column vector n*1. Can I create a Random matrix of n*8?
The function must take one value from each vector and create a matrix with 8 columns and n rows.
Jan on 24 Oct 2011
"I have a 8 column vector" sounds like a single vector. But "from each vector" might mean n vectors. Confusing.
Maurizio on 24 Oct 2011
I have 8 different variable. Each variable is a column vector (nx1).
What I need is to have as OUT a random matrix with 8 column and n rows. The value on the first OUT Column must be only the value of the first IN column

Andrei Bobrov on 24 Oct 2011
A1,A2,..,A8 - your vectors (nx1), let n = 5;
for j1 = 1:8, eval([sprintf('A%d',j1),'=randi(20,5,1)']); end
A = eval(['[',sprintf('A%d,',1:8),']'])
out=A(bsxfun(@plus,cell2mat(arrayfun(@(x)randperm(n)',(1:8),'un',0)),(0:7)*n))
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Jan on 31 Oct 2011
Maurizio on 31 Oct 2011
@JAN: I accept but because create a random Matrix but as you can see from my comment Is that there was some problem about OUT columns values

Walter Roberson on 24 Oct 2011
rv(:,1) = randomvector1;
rv(:,2) = randomvector2;
rv(:,3) = randomvector3;
....
rv(:,4) = randomvector4;
rants = zeros(8, n);
for K = 1:n
rants(:,K) = A Random Selection of One Entry Per Column from rv
end
How to do "A Random Selection of One Entry Per Column from rv" is left to you to work on in more detail. I will hint that it involves using rand().
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Maurizio on 30 Oct 2011
Can you help me what I need to write on the for loop please?
Walter Roberson on 30 Oct 2011
floor(1 + n * rand())
will give you a random row number.
If I say much more than I will be completing your assignment for you.