1 #ifndef STAN_MATH_REV_SCAL_FUN_ERF_HPP
2 #define STAN_MATH_REV_SCAL_FUN_ERF_HPP
14 class erf_vari :
public op_v_vari {
16 explicit erf_vari(vari* avi) :
17 op_v_vari(::
erf(avi->val_), avi) {
21 *
std::exp(- avi_->val_ * avi_->val_);
64 return var(
new erf_vari(a.
vi_));
fvar< T > erf(const fvar< T > &x)
Independent (input) and dependent (output) variables for gradients.
const double TWO_OVER_SQRT_PI
fvar< T > exp(const fvar< T > &x)
vari * vi_
Pointer to the implementation of this variable.