(PHP 4, PHP 5, PHP 7)
pi — Get value of pi
pi ( ) : float
Returns an approximation of pi. Also, you can use the M_PI constant which yields identical results to pi().
M_PI
The value of pi as float.
Example #1 pi() example
<?php echo pi(); // 3.1415926535898 echo M_PI; // 3.1415926535898 ?>
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