isnan

Check whether symbolic array elements are NaNs

Syntax

isnan(A)

Description

isnan(A) returns an array of the same size as A containing logical 1s (true) where the elements of A are symbolic NaNs, and logical 0s (false) where they are not.

Examples

Determine Which Elements of Symbolic Array Are NaNs

Using isnan, determine which elements of this symbolic matrix are NaNs:

isnan(sym([pi NaN Inf; 1 + i Inf + i NaN + i]))

ans =
  2×3 logical array
     0     1     0
     0     0     1

Input Arguments

A — Input value

symbolic number | symbolic variable | symbolic expression | symbolic function | symbolic array | symbolic vector | symbolic matrix

Input value, specified as a symbolic number, variable, expression, or function, or as an array, vector, or matrix of symbolic numbers, variables, expressions, functions.

Tips

• For any A, exactly one of the three quantities isfinite(A), isinf(A), or isnan(A) is 1 for each element.

• Symbolic expressions and functions containing NaN evaluate to NaN. For example, sym(NaN + i) returns symbolic NaN.