Go to main content
Oracle Developer Studio 12.5 Man Pages

Exit Print View

Updated: June 2017
 
 

slalsa (3p)

Name

slalsa - compute the SVD of the coefficient matrix in compact form. Used by sgelsd

Synopsis

SUBROUTINE SLALSA(ICOMPQ, SMLSIZ, N, NRHS, B, LDB, BX,  LDBX,  U,  LDU,
VT,  K,  DIFL,  DIFR, Z, POLES, GIVPTR, GIVCOL, LDGCOL, PERM,
GIVNUM, C, S, WORK, IWORK, INFO)


INTEGER ICOMPQ, INFO, LDB, LDBX, LDGCOL, LDU, N, NRHS, SMLSIZ

INTEGER GIVCOL(LDGCOL,*), GIVPTR(*), IWORK(*), K(*), PERM(LDGCOL,*)

REAL   B(LDB,*),   BX(LDBX,*),    C(*),    DIFL(LDU,*),    DIFR(LDU,*),
GIVNUM(LDU,*),   POLES(LDU,*),   S(*),  U(LDU,*),  VT(LDU,*),
WORK(*), Z(LDU,*)


SUBROUTINE SLALSA_64(ICOMPQ, SMLSIZ, N, NRHS, B, LDB, BX, LDBX, U, LDU,
VT,  K,  DIFL,  DIFR, Z, POLES, GIVPTR, GIVCOL, LDGCOL, PERM,
GIVNUM, C, S, WORK, IWORK, INFO)


INTEGER*8 ICOMPQ, INFO, LDB, LDBX, LDGCOL, LDU, N, NRHS, SMLSIZ

INTEGER*8 GIVCOL(LDGCOL,*), GIVPTR(*), IWORK(*), K(*), PERM(LDGCOL,*)

REAL   B(LDB,*),   BX(LDBX,*),    C(*),    DIFL(LDU,*),    DIFR(LDU,*),
GIVNUM(LDU,*),   POLES(LDU,*),   S(*),  U(LDU,*),  VT(LDU,*),
WORK(*), Z(LDU,*)


F95 INTERFACE
SUBROUTINE LALSA(ICOMPQ, SMLSIZ, N, NRHS, B, LDB, BX, LDBX, U, LDU, VT,
K,  DIFL,  DIFR,  Z,  POLES,  GIVPTR,  GIVCOL,  LDGCOL, PERM,
GIVNUM, C, S, WORK, IWORK, INFO)


REAL, DIMENSION(:,:) :: B, BX, U, VT, DIFL, DIFR, Z, POLES, GIVNUM

INTEGER :: ICOMPQ, SMLSIZ, N, NRHS, LDB, LDBX, LDU, LDGCOL, INFO

INTEGER, DIMENSION(:) :: K, GIVPTR, IWORK

REAL, DIMENSION(:) :: C, S, WORK

INTEGER, DIMENSION(:,:) :: GIVCOL, PERM


SUBROUTINE LALSA_64(ICOMPQ, SMLSIZ, N, NRHS, B, LDB, BX, LDBX, U,  LDU,
VT,  K,  DIFL,  DIFR, Z, POLES, GIVPTR, GIVCOL, LDGCOL, PERM,
GIVNUM, C, S, WORK, IWORK, INFO)


REAL, DIMENSION(:,:) :: B, BX, U, VT, DIFL, DIFR, Z, POLES, GIVNUM

INTEGER(8) :: ICOMPQ, SMLSIZ, N, NRHS, LDB, LDBX, LDU, LDGCOL, INFO

INTEGER(8), DIMENSION(:) :: K, GIVPTR, IWORK

REAL, DIMENSION(:) :: C, S, WORK

INTEGER(8), DIMENSION(:,:) :: GIVCOL, PERM


C INTERFACE
#include <sunperf.h>

void slalsa (int icompq, int smlsiz, int n, int  nrhs,  float  *b,  int
ldb,  float  *bx, int ldbx, float *u, int ldu, float *vt, int
*k, float *difl, float *difr, float  *z,  float  *poles,  int
*givptr,  int  *givcol, int ldgcol, int *perm, float *givnum,
float *c, float *s, int *info);


void slalsa_64 (long icompq, long smlsiz, long n, long nrhs, float  *b,
long  ldb,  float  *bx,  long ldbx, float *u, long ldu, float
*vt, long *k, float  *difl,  float  *difr,  float  *z,  float
*poles,  long *givptr, long *givcol, long ldgcol, long *perm,
float *givnum, float *c, float *s, long *info);

Description

Oracle Solaris Studio Performance Library                           slalsa(3P)



NAME
       slalsa  -  compute  the  SVD of the coefficient matrix in compact form.
       Used by sgelsd


SYNOPSIS
       SUBROUTINE SLALSA(ICOMPQ, SMLSIZ, N, NRHS, B, LDB, BX,  LDBX,  U,  LDU,
                 VT,  K,  DIFL,  DIFR, Z, POLES, GIVPTR, GIVCOL, LDGCOL, PERM,
                 GIVNUM, C, S, WORK, IWORK, INFO)


       INTEGER ICOMPQ, INFO, LDB, LDBX, LDGCOL, LDU, N, NRHS, SMLSIZ

       INTEGER GIVCOL(LDGCOL,*), GIVPTR(*), IWORK(*), K(*), PERM(LDGCOL,*)

       REAL   B(LDB,*),   BX(LDBX,*),    C(*),    DIFL(LDU,*),    DIFR(LDU,*),
                 GIVNUM(LDU,*),   POLES(LDU,*),   S(*),  U(LDU,*),  VT(LDU,*),
                 WORK(*), Z(LDU,*)


       SUBROUTINE SLALSA_64(ICOMPQ, SMLSIZ, N, NRHS, B, LDB, BX, LDBX, U, LDU,
                 VT,  K,  DIFL,  DIFR, Z, POLES, GIVPTR, GIVCOL, LDGCOL, PERM,
                 GIVNUM, C, S, WORK, IWORK, INFO)


       INTEGER*8 ICOMPQ, INFO, LDB, LDBX, LDGCOL, LDU, N, NRHS, SMLSIZ

       INTEGER*8 GIVCOL(LDGCOL,*), GIVPTR(*), IWORK(*), K(*), PERM(LDGCOL,*)

       REAL   B(LDB,*),   BX(LDBX,*),    C(*),    DIFL(LDU,*),    DIFR(LDU,*),
                 GIVNUM(LDU,*),   POLES(LDU,*),   S(*),  U(LDU,*),  VT(LDU,*),
                 WORK(*), Z(LDU,*)


   F95 INTERFACE
       SUBROUTINE LALSA(ICOMPQ, SMLSIZ, N, NRHS, B, LDB, BX, LDBX, U, LDU, VT,
                 K,  DIFL,  DIFR,  Z,  POLES,  GIVPTR,  GIVCOL,  LDGCOL, PERM,
                 GIVNUM, C, S, WORK, IWORK, INFO)


       REAL, DIMENSION(:,:) :: B, BX, U, VT, DIFL, DIFR, Z, POLES, GIVNUM

       INTEGER :: ICOMPQ, SMLSIZ, N, NRHS, LDB, LDBX, LDU, LDGCOL, INFO

       INTEGER, DIMENSION(:) :: K, GIVPTR, IWORK

       REAL, DIMENSION(:) :: C, S, WORK

       INTEGER, DIMENSION(:,:) :: GIVCOL, PERM


       SUBROUTINE LALSA_64(ICOMPQ, SMLSIZ, N, NRHS, B, LDB, BX, LDBX, U,  LDU,
                 VT,  K,  DIFL,  DIFR, Z, POLES, GIVPTR, GIVCOL, LDGCOL, PERM,
                 GIVNUM, C, S, WORK, IWORK, INFO)


       REAL, DIMENSION(:,:) :: B, BX, U, VT, DIFL, DIFR, Z, POLES, GIVNUM

       INTEGER(8) :: ICOMPQ, SMLSIZ, N, NRHS, LDB, LDBX, LDU, LDGCOL, INFO

       INTEGER(8), DIMENSION(:) :: K, GIVPTR, IWORK

       REAL, DIMENSION(:) :: C, S, WORK

       INTEGER(8), DIMENSION(:,:) :: GIVCOL, PERM


   C INTERFACE
       #include <sunperf.h>

       void slalsa (int icompq, int smlsiz, int n, int  nrhs,  float  *b,  int
                 ldb,  float  *bx, int ldbx, float *u, int ldu, float *vt, int
                 *k, float *difl, float *difr, float  *z,  float  *poles,  int
                 *givptr,  int  *givcol, int ldgcol, int *perm, float *givnum,
                 float *c, float *s, int *info);


       void slalsa_64 (long icompq, long smlsiz, long n, long nrhs, float  *b,
                 long  ldb,  float  *bx,  long ldbx, float *u, long ldu, float
                 *vt, long *k, float  *difl,  float  *difr,  float  *z,  float
                 *poles,  long *givptr, long *givcol, long ldgcol, long *perm,
                 float *givnum, float *c, float *s, long *info);


PURPOSE
       slalsa is an itermediate step in solving the least squares  problem  by
       computing the SVD of the coefficient matrix in compact form (The singu-
       lar vectors are computed as products of simple orthorgonal matrices).

       If ICOMPQ = 0, SLALSA applies the inverse of the left  singular  vector
       matrix  of  an  upper  bidiagonal matrix to the right hand side; and if
       ICOMPQ = 1, SLALSA applies the right  singular  vector  matrix  to  the
       right hand side. The singular vector matrices were generated in compact
       form by SLALSA.


ARGUMENTS
       ICOMPQ (input)
                 ICOMPQ is INTEGER
                 Specifies whether the  left  or  the  right  singular  vector
                 matrix is involved.
                 = 0: Left singular vector matrix,
                 = 1: Right singular vector matrix.


       SMLSIZ (input)
                 SMLSIZ is INTEGER
                 The maximum size of the subproblems at the bottom of the com-
                 putation tree.


       N (input)
                 N is INTEGER
                 The row and column dimensions of the upper bidiagonal matrix.


       NRHS (input)
                 NRHS is INTEGER
                 The number of columns of B and BX. NRHS must be at least 1.


       B (input/output)
                 B is REAL array, dimension (LDB, NRHS)
                 On  input,  B  contains  the  right  hand  sides of the least
                 squares problem in rows 1 through M.
                 On output, B contains the solution X in rows 1 through N.


       LDB (input)
                 LDB is INTEGER
                 The leading dimension of B in the calling subprogram.
                 LDB must be at least max(1, MAX(M,N)).


       BX (output)
                 BX is REAL array, dimension (LDBX, NRHS)
                 On exit, the result of applying the left  or  right  singular
                 vector matrix to B.


       LDBX (input)
                 LDBX is INTEGER
                 The leading dimension of BX.


       U (input)
                 U is REAL array, dimension (LDU, SMLSIZ)
                 On entry, U contains the left singular vector matrices of all
                 subproblems at the bottom level.


       LDU (input)
                 LDU is INTEGER, LDU = > N.
                 The leading dimension of arrays U,  VT,  DIFL,  DIFR,  POLES,
                 GIVNUM, and Z.


       VT (input)
                 VT is REAL array, dimension (LDU, SMLSIZ+1)
                 On  entry,  VT**T contains the right singular vector matrices
                 of all subproblems at the bottom level.


       K (input)
                 K is INTEGER array, dimension (N)


       DIFL (input)
                 DIFL is REAL array, dimension (LDU, NLVL)
                 where NLVL = INT(log_2 (N/(SMLSIZ+1))) + 1.


       DIFR (input)
                 DIFR is REAL array, dimension (LDU, 2*NLVL)
                 On entry, DIFL(*, I)  and  DIFR(*,  2*I-1)  record  distances
                 between singular values on the I-th level and singular values
                 on the (I-1)-th level, and DIFR(*, 2*I) record the  normaliz-
                 ing  factors  of  the right singular vectors matrices of sub-
                 problems on I-th level.


       Z (input)
                 Z is REAL array, dimension (LDU, NLVL)
                 On entry, Z(1, I) contains the components of  the  deflation-
                 adjusted  updating  row  vector  for  subproblems on the I-th
                 level.


       POLES (input)
                 POLES is REAL array, dimension (LDU, 2*NLVL).
                 On entry, POLES(*, 2*I-1: 2*I) contains the new and old  sin-
                 gular  values  involved  in the secular equations on the I-th
                 level.


       GIVPTR (input)
                 GIVPTR is INTEGER array, dimension (N)
                 On entry, GIVPTR(I) records the number  of  Givens  rotations
                 performed on the I-th problem on the computation tree.


       GIVCOL (input)
                 GIVCOL is INTEGER array, dimension (LDGCOL, 2*NLVL)
                 On entry, for each I, GIVCOL(*, 2*I-1: 2*I) records the loca-
                 tions of Givens rotations performed on the I-th level on  the
                 computation tree.


       LDGCOL (input)
                 LDGCOL is INTEGER, LDGCOL = > N.
                 The leading dimension of arrays GIVCOL and PERM.


       PERM (input)
                 PERM is INTEGER array, dimension (LDGCOL, NLVL)
                 On  entry,  PERM(*,  I) records permutations done on the I-th
                 level of the computation tree.


       GIVNUM (input)
                 GIVNUM is REAL array, dimension (LDU, 2*NLVL)
                 On entry, GIVNUM(*, 2*I-1 : 2*I) records the C- and S- values
                 of Givens rotations performed on the I-th level on the compu-
                 tation tree.


       C (input)
                 C is REAL array, dimension (N)
                 On entry, if the I-th subproblem is not square, C(I) contains
                 the  C-value  of  a Givens rotation related to the right null
                 space of the I-th subproblem.


       S (input)
                 S is REAL array, dimension (N)
                 On entry, if the I-th subproblem is not square, S(I) contains
                 the  S-value  of  a Givens rotation related to the right null
                 space of the I-th subproblem.


       WORK (output)
                 WORK is REAL array
                 The dimension must be at least N.


       IWORK (output)
                 IWORK is INTEGER array.
                 The dimension must be at least 3*N


       INFO (output)
                 INFO is INTEGER
                 = 0:  successful exit,
                 < 0:  if INFO = -i, the i-th argument had an illegal value.




                                  7 Nov 2015                        slalsa(3P)