randi

Uniformly distributed pseudo-random integer

Usages

randi(imax)

• imax should be a real positive integer scalar.
• It returns a uniformly distributed pseudo-random number taken from the set {1, 2, ..., imax}.

randi(imax,n)

• imax should be a real positive integer scalar.
• It returns an n-by-n matrix of uniformly distributed pseudo random numbers taken from the set {1, 2, ..., imax}.
• n should be a real non-negative integer scalar. If n is zero, it returns an empty array.

randi(imax,s1,s2,...,sn)

• imax should be a positive integer scalar.
• It returns an array of size [s1, s2, ..., sn]. The array contains uniformly distributed pseudo-random numbers taken from the set {1, 2, ..., imax}.
• s1, s2, ..., sN should be real non-negative integer scalars. If one of s1, s2, ..., sN is zero, it returns an empty array.

randi(imax,sizeVec)

• imax should be a positive integer.
• It returns an array of uniformly distributed pseudo-random numbers taken from the set {1, 2, ..., imax}. The array's size is specified by the size vector sizeVec.
• sizeVec should contain real non-negative elements. If an element of sizeVec is zero, it returns an empty array.

Examples

• Two methods to generate a $3\times 4\times 5$ array of integers taken from the set {1,2,3,4,5} with uniform probabilities.

Input

r1 = randi(5, 3, 4, 5);
size(r1)
r2 = randi(5, [3 4 5]);
size(r2)

Output

ans = 
 3.0000   4.0000   5.0000

ans = 
 3.0000   4.0000   5.0000

Discussion

• Since this app's algorithms for generating random numbers and initial states may be different, users should not expect this app and MATLAB to give the same sequences of pseudo-random numbers.