Stan Math Library  2.11.0
reverse mode automatic differentiation
atan.hpp
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1 #ifndef STAN_MATH_FWD_SCAL_FUN_ATAN_HPP
2 #define STAN_MATH_FWD_SCAL_FUN_ATAN_HPP
3 
4 #include <stan/math/fwd/core.hpp>
6 #include <cmath>
7 
8 namespace stan {
9  namespace math {
10 
11  template <typename T>
12  inline fvar<T> atan(const fvar<T>& x) {
13  using std::atan;
14  using stan::math::square;
15  return fvar<T>(atan(x.val_), x.d_ / (1 + square(x.val_)));
16  }
17 
18  }
19 }
20 #endif
fvar< T > atan(const fvar< T > &x)
Definition: atan.hpp:12
fvar< T > square(const fvar< T > &x)
Definition: square.hpp:15
var atan(const var &a)
Return the principal value of the arc tangent, in radians, of the specified variable (cmath)...
Definition: atan.hpp:55

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