MATLAB Function Reference

isnan - Array elements that are NaN

Syntax

TF = isnan(A)

Description

TF = isnan(A) returns an array the same size as A containing logical 1 (true) where the elements of A are NaNs and logical 0 (false) where they are not. For a complex number z, isnan(z) returns 1 if either the real or imaginary part of z is NaN, and 0 if both the real and imaginary parts are finite or Inf.

For any real A, exactly one of the three quantities isfinite(A), isinf(A), and isnan(A) is equal to one.

Examples

a = [-2  -1  0  1  2]

isnan(1./a)
Warning: Divide by zero.

ans =
     0     0     0     0     0

isnan(0./a)
Warning: Divide by zero.

ans =
     0     0     1     0     0

See Also

isfinite, isinf, is*

ismethod

isnumeric