π — Pi times / Pi ratio

Function. Keys: Alt-p. Hanzi: 周. Ranks: 0 monadic, 0 0 dyadic

πY: πY. Pervasive.

π1                ⍝ 3.141592653589793
π2                ⍝ 6.283185307179586

XπY: Xπ/Y. Angles in radians.

1π2               ⍝ 1.5707963267948966
2π3               ⍝ 2.0943951023931953

Use ○ to turn an angle into a unit-circle point.

Inverse

π⁻Y divides Y by π. Xπ⁻Y is XπY. With the right argument fixed, (π↢X)⁻Y is Y×X÷π1.

π⁻π2      ⍝ 2
2π⁻4      ⍝ π0.5
(π↢2)⁻4   ⍝ 8÷π1