(PHP 4, PHP 5, PHP 7, PHP 8)
pi — Get value of pi
Returns an approximation of pi.
Also, you can use the M_PI constant which yields
identical results to pi().
This function has no parameters.
The value of pi as float.
Example #1 pi() example
<?php
echo pi(); // 3.1415926535898
echo M_PI; // 3.1415926535898
?>