Home > lang > atan 
 fr de es it nl pl pt pt_BR mk sq ca ar fa vi ja ru zh zh_TW eo
Previous  Next  Edit  Rename  Undo  Refresh  Search  Administration  
Documentation
History
 
ATan
Syntax
Value = ATan ( fNumber AS Float ) AS Float
Value = Atn ( fNumber AS Float ) AS Float

The Atn function is the inverse of the Tan function. It computes the arc-tangent of a number. That return value is in radians and in the range from -π/2 to π/2 radians (-90 to 90 degrees)

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

Examples

PRINT ATan(0.5)

0.463647609001

The arctangent can be used to calculate the value for π as shown below:

PRINT "The Value of Pi = " ; 4 * Atn(1)

The Value of Pi = 3.14159265359

There is another function Ang (alias ATan2) which takes two arguments and returns the angle correctly over 4 quadrants.

See also

Trigonometric Functions  Ang  ATan2