Stan Math Library  2.14.0
reverse mode automatic differentiation
Phi_approx.hpp
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1 #ifndef STAN_MATH_FWD_SCAL_FUN_PHI_APPROX_HPP
2 #define STAN_MATH_FWD_SCAL_FUN_PHI_APPROX_HPP
3 
4 #include <stan/math/fwd/core.hpp>
6 #include <cmath>
7 
8 namespace stan {
9  namespace math {
10 
21  template <typename T>
22  inline fvar<T> Phi_approx(const fvar<T>& x) {
23  using std::pow;
24  return inv_logit(0.07056 * pow(x, 3.0) + 1.5976 * x);
25  }
26 
27  }
28 }
29 #endif
fvar< T > inv_logit(const fvar< T > &x)
Returns the inverse logit function applied to the argument.
Definition: inv_logit.hpp:20
fvar< T > Phi_approx(const fvar< T > &x)
Return an approximation of the unit normal cumulative distribution function (CDF).
Definition: Phi_approx.hpp:22
fvar< T > pow(const fvar< T > &x1, const fvar< T > &x2)
Definition: pow.hpp:17

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