Pi

│ Deutsch (de) │ English (en) │ suomi (fi) │ français (fr) │ русский (ru) │ 中文（中国大陆）‎ (zh_CN) │

π (greek letter pi) is the ratio of the circumference of a circle to its diameter. π is about 3.14159265358979. A full circle has 2*pi() radians.

In Pascal, system.pi is a function which returns the value of π. This gives you the chance to shadow (redefine) pi().

pi()/4 is the same as arctan(1).

See also

• system.pi
• system.arctan calculates arc tangent.