avoid to have a hard dependecy on any Linear library

Author

Ahmed Ratnani

See http://www.ratnani.org/jorek_doc/spm.html

Headers file available

Modules available

How to use it

Examples

Proposition for sparse matrix interface (Pierre)

Initialization

sll_s_sparse_matrix_init(A, spfmt, num_rows, num_cols, row, col, val)

• A derived type with arrays that describes the matrix
• spfmt indicates which sparse format is to be used
  • SLL_P_SPARSE_MATRIX_COO
  • SLL_P_SPARSE_MATRIX_CSR
  • SLL_P_SPARSE_MATRIX_CSC

num_rows indicates the number of rows in the sparse matrix. num_cols indicates the number of columns in the sparse matrix.

row is an integer parallel array of rank 1. Its length and content can vary, depending on which sparse format is used:

SLL_P_SPARSE_MATRIX_COO - row is of the same size as arrays col and val and contains row indices of the nonzero elements in array val. SLL_P_SPARSE_MATRIX_CSR - row is of size num_rows+1 and contains pointers to the beginning of each row in arrays col and val. SLL_P_SPARSE_MATRIX_CSC - row is of size num_cols+1 and contains pointers to the beginning of each column in arrays col and val. col is an integer global array of rank 1 with the same length as array val. Its use will vary, depending on which sparse format is used:

SLL_P_SPARSE_MATRIX_COO - col contains column indices of the corresponding elements stored in array val. SLL_P_SPARSE_MATRIX_CSR - col contains column indices of the corresponding elements stored in array val. SLL_P_SPARSE_MATRIX_CSC - col contains row indices of the corresponding elements in array val. val is a parallel array of rank 1, containing the nonzero elements of the sparse matrix. The storage pattern varies, depending on which sparse format is used:

SLL_P_SPARSE_MATRIX_COO - Nonzero elements can be stored in any order. SLL_P_SPARSE_MATRIX_CSR - Nonzero elements should be stored row by row, from row 1 to row num_rows. SLL_P_SPARSE_MATRIX_CSC - Nonzero elements should be stored column by column, from column 1 to column num_cols. The length of val is nnz for all three formats. This parameter represents the total number of nonzero elements in the sparse matrix.