SUBROUTINE SCSCSM( TRANSA, M, N, UNITD, DV, ALPHA, DESCRA, * VAL, INDX, PNTRB, PNTRE, * B, LDB, BETA, C, LDC, WORK, LWORK ) INTEGER*4 TRANSA, M, N, UNITD, DESCRA(5), * LDB, LDC, LWORK INTEGER*4 INDX(NNZ), PNTRB(K), PNTRE(K) REAL*4 ALPHA, BETA REAL*4 DV(M), VAL(NNZ), B(LDB,*), C(LDC,*), WORK(LWORK) SUBROUTINE DCSCSM( TRANSA, M, N, UNITD, DV, ALPHA, DESCRA, * VAL, INDX, PNTRB, PNTRE, * B, LDB, BETA, C, LDC, WORK, LWORK) INTEGER*4 TRANSA, M, N, UNITD, DESCRA(5), * LDB, LDC, LWORK INTEGER*4 INDX(NNZ), PNTRB(K), PNTRE(K) REAL*8 ALPHA, BETA REAL*8 DV(M), VAL(NNZ), B(LDB,*), C(LDC,*), WORK(LWORK) where NNZ = PNTRE(K)-PNTRB(1)
C <- alpha D inv(A) B + beta C C <- alpha D inv(A') B + beta C C <- alpha inv(A) D B + beta C C <- alpha inv(A') D B + beta C ( ' indicates matrix transpose)
TRANSA Indicates how to operate with the sparse matrix 0 : operate with matrix 1 : operate with transpose matrix M Number of rows in matrix A N Number of columns in matrix C UNITD Type of scaling: 1 : Identity matrix (argument DV[] is ignored) 2 : Scale on left (row scaling) 3 : Scale on right (column scaling) DV() Array of length M containing the diagonal entries of the diagonal matrix D. ALPHA Scalar parameter DESCRA() Descriptor argument. Five element integer array DESCRA(1) matrix structure 0 : general 1 : symmetric 2 : Hermitian 3 : Triangular 4 : Skew(Anti-Symmetric 5 : Diagonal DESCRA(2) upper/lower triangular indicator 1 : lower 2 : upper DESCRA(3) main diagonal type 0 : non-unit 1 : unit DESCRA(4) Array base (NOT IMPLEMENTED) 0 : C/C++ compatible 1 : Fortran compatible DESCRA(5) repeated indices? (NOT IMPLEMENTED) 0 : unknown 1 : no repeated indices VAL() scalar array of length NNZ containing matrix entries. INDX() integer array of length NNZ containing row indices. (row indices MUST be sorted) PNTRB() integer array of length K such that PNTRB(J)-PNTRB(1)+1 points to location in VAL of the first nonzero element in column J. PNTRE() integer array of length K such that PNTRE(J)-PNTRE(1) points to location in VAL of the last nonzero element in column J. B() rectangular array with first dimension LDB. LDB leading dimension of B BETA Scalar parameter C() rectangular array with first dimension LDC. LDC leading dimension of C WORK() scratch array of length LWORK. On exit, if LWORK = -1, WORK(1) returns the optimal LWORK. LWORK length of WORK array. LWORK should be at least M. For good performance, LWORK should generally be larger. If LWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the WORK array, returns this value as the first entry of the WORK array, and no error message related to LWORK is issued by XERBLA.
http://math.nist.gov/mcsd/Staff/KRemington/fspblas/