1 #ifndef STAN_MATH_PRIM_FUN_ONES_ARRAY_HPP
2 #define STAN_MATH_PRIM_FUN_ONES_ARRAY_HPP
3 
4 #include <stan/math/prim/err.hpp>
5 #include <vector>
6 
7 namespace stan {
8 namespace math {
9 
10 /**
11  * Return an array of ones.
12  *
13  * @param K size of the array
14  * @return An array of size K with all elements initialised to 1.
15  * @throw std::domain_error if K is negative.
16  */
ones_array(int K)17 inline std::vector<double> ones_array(int K) {
18   check_nonnegative("ones_array", "size", K);
19   return std::vector<double>(K, 1);
20 }
21 
22 }  // namespace math
23 }  // namespace stan
24 
25 #endif
26