Stan Math Library  2.8.0
reverse mode automatic differentiation
 All Classes Namespaces Files Functions Variables Typedefs Enumerator Friends Macros Groups
log.hpp
Go to the documentation of this file.
1 #ifndef STAN_MATH_FWD_SCAL_FUN_LOG_HPP
2 #define STAN_MATH_FWD_SCAL_FUN_LOG_HPP
3 
4 #include <stan/math/fwd/core.hpp>
5 
7 
8 namespace stan {
9 
10  namespace math {
11 
12  template <typename T>
13  inline
14  fvar<T>
15  log(const fvar<T>& x) {
16  using std::log;
18  if (x.val_ < 0.0)
20  else
21  return fvar<T>(log(x.val_), x.d_ / x.val_);
22  }
23  }
24 }
25 #endif
const double NOT_A_NUMBER
(Quiet) not-a-number value.
Definition: constants.hpp:56
fvar< T > log(const fvar< T > &x)
Definition: log.hpp:15
var log(const var &a)
Return the natural log of the specified variable (cmath).
Definition: log.hpp:50

     [ Stan Home Page ] © 2011–2015, Stan Development Team.