Rockwell Automation 2708-NBD VBASIC Language Development Kit - Manual (Page 78)

Appendix C
Application Library Subroutines
C–10
FullArcTangent! Returns arc tangent using numerator and denominator.
This is similar to ArcTangent (numerator/denominator) except it avoids the
divide by 0 problems and sign problems of the normal ArcTangent function.
The angle is returned in radians.
Example: Usually the numerator and denominator are y and x respectively.
When x is zero, y/x is undefined, but the FullArdcTangent of y,x is pi/2 or
pi/2 depending on the sign of y.
x! = FullArcTangent! ( numerator!, denominator! )
FUNCTION FullcTangent! ( num, den )
ArcTangent! Returns the inverse tangent in radians.
angle! = ArcTangent! ( y!/x! )
FUNCTION ArcTangent! ( x )
ArcSine! Returns the inverse sine in radians.
angle! = ArcSine! ( x! )
FUNCTION ArcSine! ( x1 )
ArcCosine! Returns the inverse cosine in radians.
angle! = ArcCosine! ( x! )
FUNCTION ArcCosine! ( x )
Tangent! Returns the tangent of an angle in radians.
x! = Tangent! ( angle! )
FUNCTION Tangent! ( x1 )
Sine! Returns the sine of an angle in radians.
y! = Sine! ( angle! )
FUNCTION Sine! ( x1 )
Cosine! Returns the cosine of an angle in radians.
x! = Cosine! ( angle! )
FUNCTION Cosine! ( x )
TangentH! Returns the hyperbolic tangent.
y! = TangentH! ( x! )
FUNCTION TangentH! ( x )