tgamma.hpp

Go to the documentation of this file.

#ifndef STAN_MATH_REV_FUN_TGAMMA_HPP
#define STAN_MATH_REV_FUN_TGAMMA_HPP
 
#include <stan/math/rev/meta.hpp>
#include <stan/math/rev/core.hpp>
#include <stan/math/prim/fun/digamma.hpp>
#include <stan/math/prim/fun/tgamma.hpp>
 
namespace stan {
namespace math {
 
inline var tgamma(const var& a) {
  return make_callback_var(tgamma(a.val()), [a](auto& vi) mutable {
    a.adj() += vi.adj() * vi.val() * digamma(a.val());
  });
}
 
template <typename T, require_var_matrix_t<T>* = nullptr>
inline auto tgamma(const T& a) {
  return make_callback_var(tgamma(a.val()), [a](auto& vi) mutable {
    a.adj().array()
        += vi.adj().array() * vi.val().array() * digamma(a.val()).array();
  });
}
 
}  // namespace math
}  // namespace stan
#endif