# ATN Function

#### Purpose:

To return the arctangent of *x*, when *x* is expressed in radians.

#### Syntax:

**ATN**(*x*)

#### Comments:

The result is within the range of -π/2 to π/2.

The expression x may be any numeric type. The evaluation of ATN is performed in single precision unless the /**d** switch is used when GW-BASIC is executed.

To convert from degrees to radians, multiply by π/180.

#### Examples:

10 INPUT X
20 PRINT ATN(X)
RUN
? 3
1.249046

Prints the arctangent of 3 radians (1.249046).