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exp2.hpp
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#ifndef STAN_MATH_REV_SCAL_FUN_EXP2_HPP
#define STAN_MATH_REV_SCAL_FUN_EXP2_HPP
#include <stan/math/rev/core.hpp>
#include <stan/math/prim/scal/fun/constants.hpp>
#include <cmath>
#include <valarray>
namespace stan {
namespace math {
namespace {
class exp2_vari : public op_v_vari {
public:
explicit exp2_vari(vari* avi) :
op_v_vari(std::pow(2.0, avi->val_), avi) {
}
void chain() {
avi_->adj_ += adj_ * val_ * stan::math::LOG_2;
}
};
}
inline var exp2(const var& a) {
return var(new exp2_vari(a.vi_));
}
}
}
#endif
stan::math::LOG_2
const double LOG_2
The natural logarithm of 2, .
Definition: constants.hpp:33
core.hpp
stan::math::var
Independent (input) and dependent (output) variables for gradients.
Definition: var.hpp:32
stan::math::var::vi_
vari * vi_
Pointer to the implementation of this variable.
Definition: var.hpp:44
stan::math::exp2
fvar< T > exp2(const fvar< T > &x)
Definition: exp2.hpp:14
constants.hpp
stan::math::pow
fvar< T > pow(const fvar< T > &x1, const fvar< T > &x2)
Definition: pow.hpp:18

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