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is_infinite

(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)

is_infinite — Checks whether a float is infinite

is_infinite(float $num): bool

Returns whether the given num is either INF or -INF.

true if num is either INF or -INF, else false.

Example #1 is_infinite() example

<?php
$inf = 1e308 * 2;

var_dump($inf, is_infinite($inf));

$negative_inf = -$inf;

var_dump($negative_inf, is_infinite($negative_inf));
?>

The above example will output:

float(INF)
bool(true)
float(-INF)
bool(true)