PHP is_infinite() 函数

is_infinite() 是一个重要的 PHP 数学函数，用于检查一个值是否为无穷大。

当值为无穷大时，返回 true；否则返回 false / 无。

语法

    bool is_infinite ( float $val );

示例1

<?php 
infinite = log(0);
var_dump(is_finite(infinite));
?>

输出：

bool(false)

示例2

<?php 
infinite = 42;
var_dump(is_finite(infinite));
?>

输出：

bool(true)

示例3

<?php 
nan = acos(2);
var_dump(is_infinite(nan));
?>

输出：

bool(false)

示例4

<?php 
nos =2;
echo "Your value is :".nos;
echo "<br>"."By using 'is_infinite()' Function your value is:".is_infinite($nos);
?>

输出：

Your value is 2
By using 'is_infinite()' Function your value is:

示例5

<?php 
nos =2000;
echo "Your value is ".nos;
echo "<br>"."By using 'is_infinite()' Function your value is:".is_infinite($nos);
?>

输出：

Your value is 2000
By using 'is_infinite()' Function your value is:

注意：当输入是无限大的时候返回true，否则返回false/没有值。

示例6

<?php 
nos =log(0);
echo "Your value is : log(0)";
echo "<br>"."By using 'is_infinite()' Function your value is:".is_infinite(nos);
?>

输出：

Your value is : log(0)
By using 'is_infinite()' Function your value is:1