MATLAB Function Reference    

Uniformly distributed random numbers and arrays



The rand function generates arrays of random numbers whose elements are uniformly distributed in the interval (0,1).

Y = rand(n) returns an n-by-n matrix of random entries. An error message appears if n is not a scalar.

Y = rand(m,n) or Y = rand([m n]) returns an m-by-n matrix of random entries.

Y = rand(m,n,p,...) or Y = rand([m n p...]) generates random arrays.

Y = rand(size(A)) returns an array of random entries that is the same size as A.

rand, by itself, returns a scalar whose value changes each time it's referenced.

s = rand('state') returns a 35-element vector containing the current state of the uniform generator. To change the state of the generator:

Resets the state to s.
Resets the generator to its initial state.
For integer j, resets the generator to its j-th state.
Resets it to a different state each time.


Example 1. R = rand(3,4) may produce

This code makes a random choice between two equally probable alternatives.

Example 2. Generate a uniform distribution of random numbers on a specified interval [a,b]. To do this, multiply the output of rand by (b-a) then add a. For example, to generate a 5-by-5 array of uniformly distributed random numbers on the interval [10,50]

See Also

randn, randperm, sprand, sprandn

  qz randn