1 #ifndef STAN_MATH_FWD_SCAL_FUN_LOG1P_EXP_HPP
2 #define STAN_MATH_FWD_SCAL_FUN_LOG1P_EXP_HPP
3 
4 #include <stan/math/fwd/core.hpp>
5 #include <stan/math/prim/scal/fun/log1p_exp.hpp>
6 
7 namespace stan {
8 namespace math {
9 
10 template <typename T>
log1p_exp(const fvar<T> & x)11 inline fvar<T> log1p_exp(const fvar<T>& x) {
12   using std::exp;
13   return fvar<T>(log1p_exp(x.val_), x.d_ / (1 + exp(-x.val_)));
14 }
15 
16 }  // namespace math
17 }  // namespace stan
18 #endif
19