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## Get pi

To get the ** pi **, use the pi function of Math::Trig module.

use Math::Trig 'pi'; pi;

Pi is the ratio of circumference (L) to diameter (R) (L/R). Pi is an irrational number and cannot be represented by a finite range of decimal numbers. The pi obtained by pi is an approximate value.

Trigonometric functions are called trigonometric functions in English, and Trig of Math::Trig is an acronym for Trigonometric function. Pi is used when specifying an angle with trigonometric functions.

Trigonometric functions are explained in detail on the following pages.

### Example

This is an example to get the pi.

use strict; use warnings; use Math::Trig 'pi'; print "(1) Get pi.\n"; print pi . "\n";