Stan Math Library  2.14.0
reverse mode automatic differentiation
log1p.hpp
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1 #ifndef STAN_MATH_REV_SCAL_FUN_LOG1P_HPP
2 #define STAN_MATH_REV_SCAL_FUN_LOG1P_HPP
3 
4 #include <stan/math/rev/core.hpp>
6 
7 namespace stan {
8  namespace math {
9 
10  namespace {
11  class log1p_vari : public op_v_vari {
12  public:
13  explicit log1p_vari(vari* avi) :
14  op_v_vari(log1p(avi->val_), avi) {
15  }
16  void chain() {
17  avi_->adj_ += adj_ / (1 + avi_->val_);
18  }
19  };
20  }
21 
32  inline var log1p(const var& a) {
33  return var(new log1p_vari(a.vi_));
34  }
35 
36  }
37 }
38 #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(const fvar< T > &x)
Definition: log1p.hpp:11

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