SUBROUTINE SGELSS( M, N, NRHS, A, LDA, B, LDB, SING, RCOND, IRANK, * WORK, LDWORK, INFO) INTEGER M, N, NRHS, LDA, LDB, IRANK, LDWORK, INFO REAL RCOND REAL A(LDA,*), B(LDB,*), SING(*), WORK(*) SUBROUTINE SGELSS_64( M, N, NRHS, A, LDA, B, LDB, SING, RCOND, * IRANK, WORK, LDWORK, INFO) INTEGER*8 M, N, NRHS, LDA, LDB, IRANK, LDWORK, INFO REAL RCOND REAL A(LDA,*), B(LDB,*), SING(*), WORK(*)
SUBROUTINE GELSS( [M], [N], [NRHS], A, [LDA], B, [LDB], SING, RCOND, * IRANK, [WORK], [LDWORK], [INFO]) INTEGER :: M, N, NRHS, LDA, LDB, IRANK, LDWORK, INFO REAL :: RCOND REAL, DIMENSION(:) :: SING, WORK REAL, DIMENSION(:,:) :: A, B SUBROUTINE GELSS_64( [M], [N], [NRHS], A, [LDA], B, [LDB], SING, * RCOND, IRANK, [WORK], [LDWORK], [INFO]) INTEGER(8) :: M, N, NRHS, LDA, LDB, IRANK, LDWORK, INFO REAL :: RCOND REAL, DIMENSION(:) :: SING, WORK REAL, DIMENSION(:,:) :: A, B
void sgelss(int m, int n, int nrhs, float *a, int lda, float *b, int ldb, float *sing, float rcond, int *irank, int *info);
void sgelss_64(long m, long n, long nrhs, float *a, long lda, float *b, long ldb, float *sing, float rcond, long *irank, long *info);
Minimize 2-norm(| b - A*x |).
using the singular value decomposition (SVD) of A. A is an M-by-N matrix which may be rank-deficient.
Several right hand side vectors b and solution vectors x can be handled in a single call; they are stored as the columns of the M-by-NRHS right hand side matrix B and the N-by-NRHS solution matrix X.
The effective rank of A is determined by treating as zero those singular values which are less than RCOND times the largest singular value.
If LDWORK = -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 LDWORK is issued by XERBLA.