dgbbrd - n band matrix A to upper bidiagonal form B by an orthogonal transformation
SUBROUTINE DGBBRD(VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, LDQ, PT, LDPT, C, LDC, WORK, INFO) CHARACTER*1 VECT INTEGER M, N, NCC, KL, KU, LDAB, LDQ, LDPT, LDC, INFO DOUBLE PRECISION AB(LDAB,*), D(*), E(*), Q(LDQ,*), PT(LDPT,*), C(LDC,*), WORK(*) SUBROUTINE DGBBRD_64(VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, LDQ, PT, LDPT, C, LDC, WORK, INFO) CHARACTER*1 VECT INTEGER*8 M, N, NCC, KL, KU, LDAB, LDQ, LDPT, LDC, INFO DOUBLE PRECISION AB(LDAB,*), D(*), E(*), Q(LDQ,*), PT(LDPT,*), C(LDC,*), WORK(*) F95 INTERFACE SUBROUTINE GBBRD(VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, LDQ, PT, LDPT, C, LDC, WORK, INFO) CHARACTER(LEN=1) :: VECT INTEGER :: M, N, NCC, KL, KU, LDAB, LDQ, LDPT, LDC, INFO REAL(8), DIMENSION(:) :: D, E, WORK REAL(8), DIMENSION(:,:) :: AB, Q, PT, C SUBROUTINE GBBRD_64(VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, LDQ, PT, LDPT, C, LDC, WORK, INFO) CHARACTER(LEN=1) :: VECT INTEGER(8) :: M, N, NCC, KL, KU, LDAB, LDQ, LDPT, LDC, INFO REAL(8), DIMENSION(:) :: D, E, WORK REAL(8), DIMENSION(:,:) :: AB, Q, PT, C C INTERFACE #include <sunperf.h> void dgbbrd(char vect, int m, int n, int ncc, int kl, int ku, double *ab, int ldab, double *d, double *e, double *q, int ldq, dou- ble *pt, int ldpt, double *c, int ldc, int *info); void dgbbrd_64(char vect, long m, long n, long ncc, long kl, long ku, double *ab, long ldab, double *d, double *e, double *q, long ldq, double *pt, long ldpt, double *c, long ldc, long *info);
Oracle Solaris Studio Performance Library dgbbrd(3P) NAME dgbbrd - reduce a real general m-by-n band matrix A to upper bidiagonal form B by an orthogonal transformation SYNOPSIS SUBROUTINE DGBBRD(VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, LDQ, PT, LDPT, C, LDC, WORK, INFO) CHARACTER*1 VECT INTEGER M, N, NCC, KL, KU, LDAB, LDQ, LDPT, LDC, INFO DOUBLE PRECISION AB(LDAB,*), D(*), E(*), Q(LDQ,*), PT(LDPT,*), C(LDC,*), WORK(*) SUBROUTINE DGBBRD_64(VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, LDQ, PT, LDPT, C, LDC, WORK, INFO) CHARACTER*1 VECT INTEGER*8 M, N, NCC, KL, KU, LDAB, LDQ, LDPT, LDC, INFO DOUBLE PRECISION AB(LDAB,*), D(*), E(*), Q(LDQ,*), PT(LDPT,*), C(LDC,*), WORK(*) F95 INTERFACE SUBROUTINE GBBRD(VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, LDQ, PT, LDPT, C, LDC, WORK, INFO) CHARACTER(LEN=1) :: VECT INTEGER :: M, N, NCC, KL, KU, LDAB, LDQ, LDPT, LDC, INFO REAL(8), DIMENSION(:) :: D, E, WORK REAL(8), DIMENSION(:,:) :: AB, Q, PT, C SUBROUTINE GBBRD_64(VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, LDQ, PT, LDPT, C, LDC, WORK, INFO) CHARACTER(LEN=1) :: VECT INTEGER(8) :: M, N, NCC, KL, KU, LDAB, LDQ, LDPT, LDC, INFO REAL(8), DIMENSION(:) :: D, E, WORK REAL(8), DIMENSION(:,:) :: AB, Q, PT, C C INTERFACE #include <sunperf.h> void dgbbrd(char vect, int m, int n, int ncc, int kl, int ku, double *ab, int ldab, double *d, double *e, double *q, int ldq, dou- ble *pt, int ldpt, double *c, int ldc, int *info); void dgbbrd_64(char vect, long m, long n, long ncc, long kl, long ku, double *ab, long ldab, double *d, double *e, double *q, long ldq, double *pt, long ldpt, double *c, long ldc, long *info); PURPOSE dgbbrd reduces a real general m-by-n band matrix A to upper bidiagonal form B by an orthogonal transformation: Q' * A * P = B. The routine computes B, and optionally forms Q or P', or computes Q'*C for a given matrix C. ARGUMENTS VECT (input) Specifies whether or not the matrices Q and P' are to be formed. = 'N': do not form Q or P'; = 'Q': form Q only; = 'P': form P' only; = 'B': form both. M (input) The number of rows of the matrix A. M >= 0. N (input) The number of columns of the matrix A. N >= 0. NCC (input) The number of columns of the matrix C. NCC >= 0. KL (input) The number of subdiagonals of the matrix A. KL >= 0. KU (input) The number of superdiagonals of the matrix A. KU >= 0. AB (input/output) DOUBLE PRECISION array, dimension(LDAB,N) On entry, the m-by- n band matrix A, stored in rows 1 to KL+KU+1. The j-th column of A is stored in the j-th column of the array AB as follows: AB(ku+1+i-j,j) = A(i,j) for max(1,j-ku)<=i<=min(m,j+kl). On exit, A is overwritten by values generated during the reduc- tion. LDAB (input) The leading dimension of the array A. LDAB >= KL+KU+1. D (output) DOUBLE PRECISION array, dimension(min(M,N)) The diagonal ele- ments of the bidiagonal matrix B. E (output) DOUBLE PRECISION array, dimension(min(M,N)-1) The superdiago- nal elements of the bidiagonal matrix B. Q (output) DOUBLE PRECISION array, dimension(LDQ,M) If VECT = 'Q' or 'B', the m-by-m orthogonal matrix Q. If VECT = 'N' or 'P', the array Q is not referenced. LDQ (input) The leading dimension of the array Q. LDQ >= max(1,M) if VECT = 'Q' or 'B'; LDQ >= 1 otherwise. PT (output) DOUBLE PRECISION array, dimension(LDPT,N) If VECT = 'P' or 'B', the n-by-n orthogonal matrix P'. If VECT = 'N' or 'Q', the array PT is not referenced. LDPT (input) The leading dimension of the array PT. LDPT >= max(1,N) if VECT = 'P' or 'B'; LDPT >= 1 otherwise. C (input/output) DOUBLE PRECISION array, dimension(LDC,NCC) On entry, an m-by- ncc matrix C. On exit, C is overwritten by Q'*C. C is not referenced if NCC = 0. LDC (input) The leading dimension of the array C. LDC >= max(1,M) if NCC > 0; LDC >= 1 if NCC = 0. WORK (workspace) DOUBLE PRECISION array, dimension(2*MAX(M,N)) INFO (output) = 0: successful exit; < 0: if INFO = -i, the i-th argument had an illegal value. 7 Nov 2015 dgbbrd(3P)