===== Atan =====
==== Format ====
**atan** ( //expression// )
==== Description ====
Computes the arc-tangent of //expression//.  Angles are expressed in radians (0 to 2pi).
==== See Also ====
[[acos|Acos]], [[asin|Asin]], [[cos|Cos]], [[degrees|Degrees]], [[radians|Radians]], [[sin|Sin]], [[tan|Tan]]