1 #ifndef STAN_MATH_PRIM_SCAL_FUN_IS_NAN_HPP 2 #define STAN_MATH_PRIM_SCAL_FUN_IS_NAN_HPP 19 inline typename std::enable_if_t<std::is_arithmetic<T>::value,
bool>
is_nan(
int isnan(const stan::math::var &a)
Checks if the given number is NaN.
int is_nan(const fvar< T > &x)
Returns 1 if the input's value is NaN and 0 otherwise.