dormhr (3p)

Name

dormhr - N matrix C with Q*C or Q**T*C or C*Q**T or C*Q.

Synopsis

SUBROUTINE DORMHR(SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU, C, LDC,
WORK, LWORK, INFO)

CHARACTER*1 SIDE, TRANS
INTEGER M, N, ILO, IHI, LDA, LDC, LWORK, INFO
DOUBLE PRECISION A(LDA,*), TAU(*), C(LDC,*), WORK(*)

SUBROUTINE DORMHR_64(SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU, C,
LDC, WORK, LWORK, INFO)

CHARACTER*1 SIDE, TRANS
INTEGER*8 M, N, ILO, IHI, LDA, LDC, LWORK, INFO
DOUBLE PRECISION A(LDA,*), TAU(*), C(LDC,*), WORK(*)




F95 INTERFACE
SUBROUTINE ORMHR(SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU, C,
LDC, WORK, LWORK, INFO)

CHARACTER(LEN=1) :: SIDE, TRANS
INTEGER :: M, N, ILO, IHI, LDA, LDC, LWORK, INFO
REAL(8), DIMENSION(:) :: TAU, WORK
REAL(8), DIMENSION(:,:) :: A, C

SUBROUTINE ORMHR_64(SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU,
C, LDC, WORK, LWORK, INFO)

CHARACTER(LEN=1) :: SIDE, TRANS
INTEGER(8) :: M, N, ILO, IHI, LDA, LDC, LWORK, INFO
REAL(8), DIMENSION(:) :: TAU, WORK
REAL(8), DIMENSION(:,:) :: A, C




C INTERFACE
#include <sunperf.h>

void dormhr(char side, char trans, int m, int n, int ilo, int ihi, dou-
ble *a, int lda, double *tau, double *c, int ldc, int *info);

void dormhr_64(char side, char trans, long m, long n,  long  ilo,  long
ihi,  double  *a, long lda, double *tau, double *c, long ldc,
long *info);

Description

Oracle Solaris Studio Performance Library                           dormhr(3P)



NAME
       dormhr  - overwrite the general real M-by-N matrix C with Q*C or Q**T*C
       or C*Q**T or C*Q.


SYNOPSIS
       SUBROUTINE DORMHR(SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU, C, LDC,
             WORK, LWORK, INFO)

       CHARACTER*1 SIDE, TRANS
       INTEGER M, N, ILO, IHI, LDA, LDC, LWORK, INFO
       DOUBLE PRECISION A(LDA,*), TAU(*), C(LDC,*), WORK(*)

       SUBROUTINE DORMHR_64(SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU, C,
             LDC, WORK, LWORK, INFO)

       CHARACTER*1 SIDE, TRANS
       INTEGER*8 M, N, ILO, IHI, LDA, LDC, LWORK, INFO
       DOUBLE PRECISION A(LDA,*), TAU(*), C(LDC,*), WORK(*)




   F95 INTERFACE
       SUBROUTINE ORMHR(SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU, C,
              LDC, WORK, LWORK, INFO)

       CHARACTER(LEN=1) :: SIDE, TRANS
       INTEGER :: M, N, ILO, IHI, LDA, LDC, LWORK, INFO
       REAL(8), DIMENSION(:) :: TAU, WORK
       REAL(8), DIMENSION(:,:) :: A, C

       SUBROUTINE ORMHR_64(SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU,
              C, LDC, WORK, LWORK, INFO)

       CHARACTER(LEN=1) :: SIDE, TRANS
       INTEGER(8) :: M, N, ILO, IHI, LDA, LDC, LWORK, INFO
       REAL(8), DIMENSION(:) :: TAU, WORK
       REAL(8), DIMENSION(:,:) :: A, C




   C INTERFACE
       #include <sunperf.h>

       void dormhr(char side, char trans, int m, int n, int ilo, int ihi, dou-
                 ble *a, int lda, double *tau, double *c, int ldc, int *info);

       void dormhr_64(char side, char trans, long m, long n,  long  ilo,  long
                 ihi,  double  *a, long lda, double *tau, double *c, long ldc,
                 long *info);



PURPOSE
       dormhr overwrites the general real M-by-N matrix C with

                       SIDE = 'L'     SIDE = 'R'
       TRANS = 'N':      Q * C          C * Q
       TRANS = 'T':      Q**T * C       C * Q**T

       where Q is a real orthogonal matrix of order nq, with nq = m if SIDE  =
       'L'  and  nq  = n if SIDE = 'R'. Q is defined as the product of IHI-ILO
       elementary reflectors, as returned by DGEHRD:

       Q = H(ilo) H(ilo+1) . . . H(ihi-1).


ARGUMENTS
       SIDE (input)
                 = 'L': apply Q or Q**T from the Left;
                 = 'R': apply Q or Q**T from the Right.


       TRANS (input)
                 = 'N':  No transpose, apply Q;
                 = 'T':  Transpose, apply Q**T.


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


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


       ILO (input)
                 ILO and IHI must have the same values as in the previous call
                 of DGEHRD. Q is equal to the unit matrix except in the subma-
                 trix Q(ilo+1:ihi,ilo+1:ihi).  If SIDE = 'L', then 1 <= ILO <=
                 IHI  <=  M,  if  M > 0, and ILO = 1 and IHI = 0, if M = 0; if
                 SIDE = 'R', then 1 <= ILO <= IHI <= N, if N > 0, and ILO =  1
                 and IHI = 0, if N = 0.


       IHI (input)
                 See the description of ILO.


       A (input) (LDA,M) if SIDE = 'L' (LDA,N) if SIDE = 'R' The vectors which
                 define the elementary reflectors, as returned by DGEHRD.


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


       TAU (input)
                 (M-1)  if  SIDE = 'L' (N-1) if SIDE = 'R' TAU(i) must contain
                 the scalar  factor  of  the  elementary  reflector  H(i),  as
                 returned by DGEHRD.


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


       WORK (workspace)
                 On exit, if INFO = 0, WORK(1) returns the optimal LWORK.


       LWORK (input)
                 The dimension of the array WORK.  If SIDE  =  'L',  LWORK  >=
                 max(1,N); if SIDE = 'R', LWORK >= max(1,M).  For optimum per-
                 formance LWORK >= N*NB if SIDE = 'L', and LWORK  >=  M*NB  if
                 SIDE = 'R', where NB is the optimal blocksize.

                 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.


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




                                  7 Nov 2015                        dormhr(3P)