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ADValued-> Arithmetic std_math_ad MathOther CondExp Discrete

MathOther-> abs atan2 erf pow

atan2-> Atan2.cpp

Headings-> Syntax Purpose y x theta Operation Sequence Example

AD Two Argument Inverse Tangent Function
Syntax
theta = atan2(y, x)

Purpose
Determines an angle  \theta \in [ - \pi , + \pi ] such that  \[
\begin{array}{rcl}
     \sin ( \theta )  & = & y / \sqrt{ x^2 + y^2 }  \\
     \cos ( \theta )  & = & x / \sqrt{ x^2 + y^2 }
\end{array}
\] 

y
The argument y has one of the following prototypes
     const AD<Base>               &y
     const VecAD<Base>::reference &y

x
The argument x has one of the following prototypes
     const AD<Base>               &x
     const VecAD<Base>::reference &x

theta
The result theta has prototype
     AD<Base> theta

Operation Sequence
The AD of Base operation sequence used to calculate theta is independent of x and y.

Example
The file Atan2.cpp contains an example and test of this function. It returns true if it succeeds and false otherwise.

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Input File: cppad/local/atan2.hpp