is_finite()

is_finite() — Checks whether a float is finite.

Built-in function of PHP 8.5. The manual lists it as available in PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8. This page is the reference card: signature, parameters and return value, plus the changelog and the example the manual provides.

Signature

is_finite(float $num): bool

Parameters

Return value

true if num is none of NAN, INF, -INF, else false.

Example

A runnable snippet:

$float = 1.2345; var_dump($float, is_finite($float)); $nan = sqrt(-1); var_dump($nan, is_finite($nan)); $inf = 1e308 * 2; var_dump($inf, is_finite($inf));

Output:

float(1.2345) bool(true) float(NAN) bool(false) float(INF) bool(false)

See also

is_infinite(), is_nan()

All PHP 8.5 built-in functions

Reference card built from the PHP manual page is_finite() (PHP documentation, CC BY 3.0). The page is generated from the manual, so the wording of the parameter and return value text follows php.net.