For symmetric matrices only the lower triangular values are given, which we need to map towards a full matrix, as the current implementations of the *sparse.CSR has no approaches for using symmetric systems (yet).
Variants of the coordinate format are defined for matrices with complex and integer entries, as well as for those in which only the position of the nonzero entries is prescribed (pattern matrices). (These would be indicated by changing real to complex, integer, or pattern, respectively, on the header line). Additional variants are defined for cases in which symmetries can be used to significantly reduce the size of the data: symmetric, skew-symmetric and Hermitian. In these cases, only entries in the lower triangular portion need be supplied. In the skew-symmetric case the diagonal entries are zero, and hence they too are omitted. (These would be indicated by changing general to symmetric, skew-symmetric, or hermitian, respectively, on the header line).
For symmetric matrices only the lower triangular values are given, which we need to map towards a full matrix, as the current implementations of the
*sparse.CSRhas no approaches for using symmetric systems (yet).