← All built-ins / is_nan()
is_nan()
is_nan(mixed $number): bool
Parameters
| Name | Type | Description |
|---|---|---|
| $number | float | value to test |
Return value
true for NaN.
Example
var_dump(is_nan(sqrt(-1))); var_dump(is_nan(1.5));
bool(true) bool(false)
| Name | Type | Description |
|---|---|---|
| $number | float | value to test |
true for NaN.
var_dump(is_nan(sqrt(-1))); var_dump(is_nan(1.5));
bool(true) bool(false)