Stan Math Library  2.15.0
reverse mode automatic differentiation
csr_to_dense_matrix.hpp
Go to the documentation of this file.
1 #ifndef STAN_MATH_PRIM_MAT_FUN_CSR_TO_DENSE_MATRIX_HPP
2 #define STAN_MATH_PRIM_MAT_FUN_CSR_TO_DENSE_MATRIX_HPP
3 
10 #include <vector>
11 
12 namespace stan {
13  namespace math {
14 
35  template <typename T>
36  inline Eigen::Matrix<T, Eigen::Dynamic, Eigen::Dynamic>
38  int n,
39  const Eigen::Matrix<T, Eigen::Dynamic, 1>& w,
40  const std::vector<int>& v,
41  const std::vector<int>& u) {
42  using Eigen::Dynamic;
43  using Eigen::Matrix;
44 
45  check_positive("csr_to_dense_matrix", "m", m);
46  check_positive("csr_to_dense_matrix", "n", n);
47  check_size_match("csr_to_dense_matrix", "m", m, "u", u.size()-1);
48  check_size_match("csr_to_dense_matrix", "w", w.size(), "v", v.size());
49  check_size_match("csr_to_dense_matrix", "u/z",
50  u[m-1] + csr_u_to_z(u, m - 1) - 1,
51  "v", v.size());
52  for (size_t i = 0; i < v.size(); ++i)
53  check_range("csr_to_dense_matrix", "v[]", n, v[i]);
54 
55  Matrix<T, Dynamic, Dynamic> result(m, n);
56  result.setZero();
57  for (int row = 0; row < m; ++row) {
58  int row_end_in_w = (u[row] - stan::error_index::value)
59  + csr_u_to_z(u, row);
60  check_range("csr_to_dense_matrix", "w", w.size(), row_end_in_w);
61  for (int nze = u[row] - stan::error_index::value;
62  nze < row_end_in_w; ++nze) {
63  // row is row index, v[nze] is column index. w[nze] is entry value.
64  check_range("csr_to_dense_matrix", "j", n, v[nze]);
65  result(row, v[nze] - stan::error_index::value) = w(nze);
66  }
67  }
68  return result;
69  } // end of csr_format group
71 
72  }
73 }
74 #endif
void check_range(const char *function, const char *name, int max, int index, int nested_level, const char *error_msg)
Check if specified index is within range.
Definition: check_range.hpp:28
int csr_u_to_z(const std::vector< int > &u, int i)
Return the z vector computed from the specified u vector at the index for the z vector.
Definition: csr_u_to_z.hpp:26
void check_size_match(const char *function, const char *name_i, T_size1 i, const char *name_j, T_size2 j)
Check if the provided sizes match.
Eigen::Matrix< T, 1, Eigen::Dynamic > row(const Eigen::Matrix< T, Eigen::Dynamic, Eigen::Dynamic > &m, size_t i)
Return the specified row of the specified matrix, using start-at-1 indexing.
Definition: row.hpp:26
void check_positive(const char *function, const char *name, const T_y &y)
Check if y is positive.
Eigen::Matrix< T, Eigen::Dynamic, Eigen::Dynamic > csr_to_dense_matrix(int m, int n, const Eigen::Matrix< T, Eigen::Dynamic, 1 > &w, const std::vector< int > &v, const std::vector< int > &u)
Construct a dense Eigen matrix from the CSR format components.

     [ Stan Home Page ] © 2011–2016, Stan Development Team.