How to generate uniformly distributed random integers?

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I've been using "ceil(4*rand)" to generate random integers from 1 to 4. But when I tried to check the uniformity, I found that I do not get a probability of 0.25 and instead have p(1)=0.24997, p(2)=0.25102, p(3)=0.24949 and p(4)=0.24951 after generating 10,00,000 values. Is it good enough to say that it's uniform?

Accepted Answer

the cyclist
the cyclist on 25 Jul 2011
Yes. You should not expect to get exactly 25% of each, every time. That is expected behavior of random numbers.
FYI, it may be more convenient for you to use the randi() function to do what you are doing.
  1 Comment
Walter Roberson
Walter Roberson on 25 Jul 2011
the cyclist is correct. Please see also the description in http://www.mathworks.com/matlabcentral/answers/12307-how-to-generate-a-uniform-random-variable-in-the-interval-1-1-with-mean-zero

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More Answers (2)

Pannir Selvam Elamvazhuthi
Thanks Cyclist and Walter Roberson. Sorry to have responded late.
  1 Comment
the cyclist
the cyclist on 29 Aug 2011
No problem on the late response. However, you should consider deleting this "answer" (because it is not answer), and making it a comment on my answer.

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Sergio Enrique Pinto Castillo
Edited: Sergio Enrique Pinto Castillo on 28 Jul 2020
I think the answer is:
Num = 1000;
vec = randi([1 Num],1,Num);
This instruction generate a vector with random uniformly distributed integers between 1 and 1000

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