dorm2l (3p)

Name

dorm2l - multiply a general matrix by the orthogonal matrix from a QL factorization determined by sgeqlf (unblocked algorithm)

Synopsis

SUBROUTINE DORM2L( SIDE, TRANS, M, N, K, A, LDA,  TAU,  C,  LDC,  WORK,
INFO )


CHARACTER*1 SIDE, TRANS

INTEGER INFO, K, LDA, LDC, M, N

DOUBLE PRECISION A(LDA,*), C(LDC,*), TAU(*), WORK(*)


SUBROUTINE  DORM2L_64( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK,
INFO )


CHARACTER*1 SIDE, TRANS

INTEGER*8 INFO, K, LDA, LDC, M, N

DOUBLE PRECISION A(LDA,*), C(LDC,*), TAU(*), WORK(*)


F95 INTERFACE
SUBROUTINE ORM2L( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, INFO
)


INTEGER :: M, N, K, LDA, LDC, INFO

CHARACTER(LEN=1) :: SIDE, TRANS

REAL(8), DIMENSION(:,:) :: A, C

REAL(8), DIMENSION(:) :: TAU, WORK


SUBROUTINE  ORM2L_64(  SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK,
INFO )


INTEGER(8) :: M, N, K, LDA, LDC, INFO

CHARACTER(LEN=1) :: SIDE, TRANS

REAL(8), DIMENSION(:,:) :: A, C

REAL(8), DIMENSION(:) :: TAU, WORK


C INTERFACE
#include <sunperf.h>

void dorm2l (char side, char trans, int m, int n, int k, double *a, int
lda, double *tau, double *c, int ldc, int *info);


void  dorm2l_64  (char side, char trans, long m, long n, long k, double
*a, long lda, double *tau, double *c, long ldc, long *info);

Description

Oracle Solaris Studio Performance Library                           dorm2l(3P)



NAME
       dorm2l  -  multiply a general matrix by the orthogonal matrix from a QL
       factorization determined by sgeqlf (unblocked algorithm)


SYNOPSIS
       SUBROUTINE DORM2L( SIDE, TRANS, M, N, K, A, LDA,  TAU,  C,  LDC,  WORK,
                 INFO )


       CHARACTER*1 SIDE, TRANS

       INTEGER INFO, K, LDA, LDC, M, N

       DOUBLE PRECISION A(LDA,*), C(LDC,*), TAU(*), WORK(*)


       SUBROUTINE  DORM2L_64( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK,
                 INFO )


       CHARACTER*1 SIDE, TRANS

       INTEGER*8 INFO, K, LDA, LDC, M, N

       DOUBLE PRECISION A(LDA,*), C(LDC,*), TAU(*), WORK(*)


   F95 INTERFACE
       SUBROUTINE ORM2L( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, INFO
                 )


       INTEGER :: M, N, K, LDA, LDC, INFO

       CHARACTER(LEN=1) :: SIDE, TRANS

       REAL(8), DIMENSION(:,:) :: A, C

       REAL(8), DIMENSION(:) :: TAU, WORK


       SUBROUTINE  ORM2L_64(  SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK,
                 INFO )


       INTEGER(8) :: M, N, K, LDA, LDC, INFO

       CHARACTER(LEN=1) :: SIDE, TRANS

       REAL(8), DIMENSION(:,:) :: A, C

       REAL(8), DIMENSION(:) :: TAU, WORK


   C INTERFACE
       #include <sunperf.h>

       void dorm2l (char side, char trans, int m, int n, int k, double *a, int
                 lda, double *tau, double *c, int ldc, int *info);


       void  dorm2l_64  (char side, char trans, long m, long n, long k, double
                 *a, long lda, double *tau, double *c, long ldc, long *info);


PURPOSE
       dorm2l overwrites the general real m by n matrix C with

       Q * C  if SIDE = 'L' and TRANS = 'N', or

       Q**T * C  if SIDE = 'L' and TRANS = 'T', or

       C * Q  if SIDE = 'R' and TRANS = 'N', or

       C * Q**T if SIDE = 'R' and TRANS = 'T',

       where Q is a real orthogonal matrix defined as the product of k elemen-
       tary reflectors

       Q = H(k) . . . H(2) H(1)

       as  returned by DGEQLF. Q is of order m if SIDE = 'L' and of order n if
       SIDE = 'R'.


ARGUMENTS
       SIDE (input)
                 SIDE is CHARACTER*1
                 = 'L': apply Q or Q**T from the Left
                 = 'R': apply Q or Q**T from the Right


       TRANS (input)
                 TRANS is CHARACTER*1
                 = 'N': apply Q  (No transpose)
                 = 'T': apply Q**T (Transpose)


       M (input)
                 M is INTEGER
                 The number of rows of the matrix C. M >= 0.


       N (input)
                 N is INTEGER
                 The number of columns of the matrix C. N >= 0.


       K (input)
                 K is INTEGER
                 The number of elementary reflectors whose product defines
                 the matrix Q.
                 If SIDE = 'L', M >= K >= 0;
                 if SIDE = 'R', N >= K >= 0.


       A (input)
                 A is DOUBLE PRECISION array, dimension (LDA,K)
                 The i-th column must contain the vector which defines the
                 elementary reflector H(i), for i = 1,2,...,k, as returned by
                 DGEQLF in the last k columns of its array argument A.
                 A is modified by the routine but restored on exit.


       LDA (input)
                 LDA is INTEGER
                 The leading dimension of the array A.
                 If SIDE = 'L', LDA >= max(1,M);
                 if SIDE = 'R', LDA >= max(1,N).


       TAU (input)
                 TAU is DOUBLE PRECISION array, dimension (K)
                 TAU(i) must contain the scalar factor of the elementary
                 reflector H(i), as returned by DGEQLF.


       C (input/output)
                 C is DOUBLE PRECISION array, dimension (LDC,N)
                 On entry, the m by n matrix C.
                 On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or  C*Q.


       LDC (input)
                 LDC is INTEGER
                 The leading dimension of the array C. LDC >= max(1,M).


       WORK (output)
                 WORK is DOUBLE PRECISION array, dimension
                 (N) if SIDE = 'L',
                 (M) if SIDE = 'R'


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




                                  7 Nov 2015                        dorm2l(3P)