ATAN function (ODBC compatible)

Syntax

ATAN ( expression )

Description

The scalar function ATAN returns the arctangent of expression.

Example

select atan (1) * (180/ pi()) 'Arctangent in degrees' from syscalctable;

ARCTANGENT IN DE

----------------

45.000000000000000

1 record selected

select atan (1) 'Arctangent in radians' from syscalctable;

ARCTANGENT IN RA

----------------

0.785398163397448

1 record selected

Notes

ATAN takes the ratio (expression) of two sides of a right triangle and returns the corresponding angle. The ratio is the length of the side opposite the angle divided by the length of the side adjacent to the angle.

The result is expressed in radians and is in the range -Pi/2 to Pi/2 radians. To convert degrees to radians, multiply degrees by Pi/180. To convert radians to degrees, multiply radians by 180/Pi.

- Expression must be in the range -1 to 1.
- Expression must evaluate to an approximate numeric data type.