# Reference/atan

From Kx Wiki

## Contents |

## atan (arc tangent function)

The `atan` function computes the arc tangent of its argument; that is the value whose tangent is the given argument. The result is in radians and lies between -PI/2 and PI/2 (the range is approximate due to rounding errors).

## Syntax

q)a:atan 0.5

## Example

q)atan 0.5 0.4636476 q)atan 42 1.546991

## See also

For a complete list of functions, see the kdb+ Function Reference.