1 #ifndef STAN_MATH_FWD_SCAL_FUN_LOG1M_HPP
2 #define STAN_MATH_FWD_SCAL_FUN_LOG1M_HPP
3 
4 #include <stan/math/fwd/core.hpp>
5 #include <stan/math/prim/scal/fun/log1m.hpp>
6 #include <stan/math/prim/scal/fun/constants.hpp>
7 
8 namespace stan {
9 namespace math {
10 
11 template <typename T>
log1m(const fvar<T> & x)12 inline fvar<T> log1m(const fvar<T>& x) {
13   return fvar<T>(log1m(x.val_), -x.d_ / (1 - x.val_));
14 }
15 }  // namespace math
16 }  // namespace stan
17 #endif
18