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PHP is_nan () function

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Examples

Determine whether a non-numeric value:

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

Running instance »

Definition and Usage

is_nan () function to determine whether a non-numeric value.

If the value of non-designated value, the function returns true (1). Otherwise, it returns false / nothing.


grammar

is_nan( value );

参数 描述
value 必需。规定要检查的值。

technical details

return value: If a non-numeric value, it returns TRUE. Otherwise, it returns FALSE.
Return type: Boolean
PHP version: 4.2+


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