PHP is_nan()Functions
Examples
Determine whether a value is not a number:
<?php
echo is_nan(200) . "<br>";
echo is_nan(acos(1.01));
?>
echo is_nan(200) . "<br>";
echo is_nan(acos(1.01));
?>
Run example »
Definition and Usage
The is_nan() function determines whether a value is not a number.
If the specified value is not a number, this function returns true (1). Otherwise, it will return false/nothing.
Syntax
is_nan(value);
| Parameter | Description |
|---|---|
| value | Required. Specifies the value to check. |
Technical Details
| Return value: | Ifvalueit is not a number, then returns TRUE. Otherwise, returns FALSE. |
|---|---|
| Return type: | Boolean |
| PHP Version: | 4.2+ |
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