1 #ifndef STAN_MATH_REV_CORE_OPERATOR_SUBTRACTION_HPP
2 #define STAN_MATH_REV_CORE_OPERATOR_SUBTRACTION_HPP
8 #include <boost/math/special_functions/fpclassify.hpp>
15 class subtract_vv_vari :
public op_vv_vari {
17 subtract_vv_vari(vari* avi, vari* bvi) :
18 op_vv_vari(avi->val_ - bvi->val_, avi, bvi) {
23 avi_->adj_ = std::numeric_limits<double>::quiet_NaN();
24 bvi_->adj_ = std::numeric_limits<double>::quiet_NaN();
32 class subtract_vd_vari :
public op_vd_vari {
34 subtract_vd_vari(vari* avi,
double b) :
35 op_vd_vari(avi->val_ - b, avi, b) {
40 avi_->adj_ = std::numeric_limits<double>::quiet_NaN();
46 class subtract_dv_vari :
public op_dv_vari {
48 subtract_dv_vari(
double a, vari* bvi) :
49 op_dv_vari(a - bvi->val_, a, bvi) {
54 bvi_->adj_ = std::numeric_limits<double>::quiet_NaN();
100 return var(
new subtract_vv_vari(a.
vi_, b.
vi_));
117 return var(
new subtract_vd_vari(a.
vi_, b));
132 return var(
new subtract_dv_vari(a, b.
vi_));
fvar< T > operator-(const fvar< T > &x1, const fvar< T > &x2)
Independent (input) and dependent (output) variables for gradients.
bool isnan(const stan::math::var &v)
Checks if the given number is NaN.
vari * vi_
Pointer to the implementation of this variable.