Stan Math Library  2.11.0
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>
7 #include <valarray>
8 
9 namespace stan {
10  namespace math {
11 
12  namespace {
13  class log1p_vari : public op_v_vari {
14  public:
15  explicit log1p_vari(vari* avi) :
16  op_v_vari(stan::math::log1p(avi->val_), avi) {
17  }
18  void chain() {
19  avi_->adj_ += adj_ / (1 + avi_->val_);
20  }
21  };
22  }
23 
34  inline var log1p(const stan::math::var& a) {
35  return var(new log1p_vari(a.vi_));
36  }
37 
38  }
39 }
40 #endif
Independent (input) and dependent (output) variables for gradients.
Definition: var.hpp:31
vari * vi_
Pointer to the implementation of this variable.
Definition: var.hpp:43
fvar< T > log1p(const fvar< T > &x)
Definition: log1p.hpp:16

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