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PHP is_nan() Function

PHP Math Reference

Complete PHP Math Reference

Definition and Usage

The is_nan() function returns true if the specified value is "not a number", otherwise it returns nothing.

Syntax

is_nan(x)

Parameter	Description
x	Required. The value to check

Example

<?php
echo is_nan(200) . "<br />";
echo is_nan(acos(1.01));
?>

The output of the code above will be:

1

PHP Math Reference

Complete PHP Math Reference

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