4.14: Logical Functions for Arrays

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Page ID: 136632

Zara Noroozi
Irvine Valley College

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MATLAB also includes functions that test the type or properties of an array. These functions return logical values: true or false.

Function	Purpose
ischar(A)	Tests whether A is a character array
islogical(A)	Tests whether A is a logical array
isnumeric(A)	Tests whether A is numeric
isinteger(A)	Tests whether A is an integer array
isfloat(A)	Tests whether A is a floating-point array
isreal(A)	Tests whether A contains real values
isa(A, className)	Tests whether A belongs to a specific class
isprime(A)	Returns true for prime values in A
isfinite(A)	Returns true for finite values in A
isinf(A)	Returns true for infinite values in A
isnan(A)	Returns true for NaN values in A
isequal(A,B)	Tests whether arrays have the same contents

These functions are useful for checking data before performing calculations. For example, you may want to confirm that an input is numeric before trying to calculate with it.

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