10.6 atan() and atan2()

Prototypes		Header File(s)
`template <class T>`
`RWMathVec<T>`	`atan(const RWMathVec<T>&)`	`<rw/math/mathvec.h>`
`RWMathVec<T>`	`atan2(const RWMathVec<T>&` `const RWMathVec<T>&)`	`<rw/math/mathvec.h>`
`RWGenMat<T>`	`atan(const RWGenMat<T>&)`	`<rw/math/genmat.h>`
`RWGenMat<T>`	`atan2(const RWGenMat<T>&,` `const RWGenMat<T>&)`	`<rw/math/genmat.h>`
`RWMathArray<T>`	`atan(const RWMathArray<T>&)`	`<rw/math/mtharray.h>`
`RWMathArray<T>`	`atan2(const RWMathArray<T>&,` `const RWMathArray<T>&)`	`<rw/math/mtharray.h>`

10.6.1 Description

The function atan() takes x and returns y of arc tangents (in radians), such that y_i = tan^-1x_i, where -/2 < y_i /2.

The function atan2() takes two arguments and returns quadrant correct arc tangents z (in radians), such that z_i = tan^-1 ( x_i/ y_i ). For each element i, the expression atan2(x_i, y_i) is mathematically equivalent to:

At least one of the arguments x_i or y_i must be nonzero.