Stan Math Library  2.15.0
reverse mode automatic differentiation
log1p_exp.hpp
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1 #ifndef STAN_MATH_REV_SCAL_FUN_LOG1P_EXP_HPP
2 #define STAN_MATH_REV_SCAL_FUN_LOG1P_EXP_HPP
3 
4 #include <stan/math/rev/core.hpp>
7 
8 namespace stan {
9  namespace math {
10 
11  namespace {
12  class log1p_exp_v_vari : public op_v_vari {
13  public:
14  explicit log1p_exp_v_vari(vari* avi) :
15  op_v_vari(log1p_exp(avi->val_),
16  avi) {
17  }
18  void chain() {
19  avi_->adj_ += adj_ * calculate_chain(avi_->val_, val_);
20  }
21  };
22  }
23 
28  inline var log1p_exp(const var& a) {
29  return var(new log1p_exp_v_vari(a.vi_));
30  }
31 
32  }
33 }
34 #endif
Independent (input) and dependent (output) variables for gradients.
Definition: var.hpp:30
vari * vi_
Pointer to the implementation of this variable.
Definition: var.hpp:42
fvar< T > log1p_exp(const fvar< T > &x)
Definition: log1p_exp.hpp:13
double calculate_chain(double x, double val)

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