mod (MATLAB Function Reference)

mod	Examples See Also

Modulus (signed remainder after division)

Syntax

M = mod(X,Y)

Definition

mod(x,y) is x mod y.

Description

M = mod(X,Y)

returns the remainder X - Y.*floor(X./Y) for nonzero Y, and returns X otherwise. mod(X,Y) always differs from X by a multiple of Y.

Remarks

So long as operands X and Y are of the same sign, the function mod(X,Y) returns the same result as does rem(X,Y). However, for positive X and Y,

mod(-x,y) = rem(-x,y)+y

The mod function is useful for congruence relationships:
x and y are congruent (mod m) if and only if mod(x,m) == mod(y,m).

Examples

mod(13,5)

ans =
     3

mod([1:5],3)

ans =
     1     2     0     1     2 

mod(magic(3),3)

ans =
     2     1     0
     0     2     1
     1     0     2

Limitations

Arguments X and Y should be integers. Due to the inexact representation of floating-point numbers on a computer, real (or complex) inputs may lead to unexpected results.