SscIc0 SscIcSolve SscSsorSolve SsrIc0 SsrIcSolve SsrSsorSolve

SscIcSolve() Sub SscIcSolve ( N As  Long, Val() As  Double, Colptr() As  Long, Rowind() As  Long, Idiag() As  Long, B() As  Double, X() As  Double, Optional Info As  Long, Optional ByVal Uplo As  String = "U", Optional Base As  Long = -1  ) Incomplete Cholesky decomposition preconditioner (IC) (symmetric positive definite matrix) (CSC) Purpose This routine is the incomplete Cholesky decomposition preconditioner (IC) for the symmetric positive definite coefficient matrix of the sparse linear equations. It solves the equation Mx = b, where M is the preconditioner matrix (L*D*L^T or U^T*D*U). Parameters [in] N Dimension of preconditioner matrix. (N >= 0) (if N = 0, returns without computation) [in] Val() Array Val(LVal - 1) (LVal >= Nnz) (Nnz is number of nonzero elements) Values of non-zero elements of preconditioner matrix. [in] Colptr() Array Colptr(LColptr - 1) (LColptr >= N + 1) Column pointers of preconditioner matrix. [in] Rowind() Array Rowind(LRowind - 1) (LRowind >= Nnz) Row indices of preconditioner matrix. [in] Idiag() Array Idiag(LIdiag) (LIdiag >= N) Indices of diagonal elements. [in] B() Array B(LB - 1) (LB >= N) Right hand side vector b. [out] X() Array X(LX - 1) (LX >= N) Solution vector x. [out] Info (Optional) = 0: Successful exit. = i < 0: The (-i)-th argument is invalid. = j > 0: Matrix is singular (j-th diagonal element is zero). [in] Uplo (Optional) = "U": Upper trianglar matrix U and diagonal matrix D are stored as the preconditioner matrix. = "L": Lower trianglar matrix L and diagonal matrix D are stored as the preconditioner matrix. (default = "U") [in] Base (Optional) Indexing of Colptr() and Rowind(). = 0: Zero-based (C style) indexing: Starting index is 0. = 1: One-based (Fortran style) indexing: Starting index is 1. (default: Assumes 1 if Colptr(0) = 1, 0 otherwise) Example Program See example of SscIc0.