Atan Function

Atan Function

Class

System.Math

Syntax

 Math.Atan(   d   )

d (required; Double or any valid numeric expression): A number representing a tangent

Return Value

A Double that is the arctangent in radians of d , in the range -pi/2 to pi/2

Description

Takes the ratio of two sides of a right triangle ( d ) and returns the corresponding angle in radians. The ratio is the length of the side opposite the angle divided by the length of the side adjacent to the angle.

Rules at a Glance

If d is out of range, the function returns NaN .
This is a Shared member, so it can be used without creating any objects.

Example

 Private Sub Main(  )     Dim dblSideAdj As Double     Dim dblSideOpp As Double     Dim dblRatio As Double     Dim dblAtangent As Double          dblSideAdj = 50.25     dblSideOpp = 75.5          dblRatio = dblSideOpp / dblSideAdj     dblAtangent = Math.Atan(dblRatio)     'convert from radians to degrees     dblDegrees = dblAtangent * (180 / 3.142)     MsgBox dblDegrees & " Degrees" End Sub

Programming Tips and Gotchas

To convert radians to degrees, multiply radians by 180/pi.
Do not confuse Atan with the cotangent. Atan is the inverse trigonometric function of Tan , whereas the cotangent is the reciprocal of the tangent.

VB.NET/VB 6 Differences

The Atan function corresponds to the VB 6 Atn intrinsic function.