Scroll to navigation

/home/abuild/rpmbuild/BUILD/lapack-3.12.0/SRC/sopmtr.f(3) Library Functions Manual /home/abuild/rpmbuild/BUILD/lapack-3.12.0/SRC/sopmtr.f(3)

NAME

/home/abuild/rpmbuild/BUILD/lapack-3.12.0/SRC/sopmtr.f

SYNOPSIS

Functions/Subroutines


subroutine SOPMTR (side, uplo, trans, m, n, ap, tau, c, ldc, work, info)
SOPMTR

Function/Subroutine Documentation

subroutine SOPMTR (character side, character uplo, character trans, integer m, integer n, real, dimension( * ) ap, real, dimension( * ) tau, real, dimension( ldc, * ) c, integer ldc, real, dimension( * ) work, integer info)

SOPMTR

Purpose:

!>
!> SOPMTR 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
!> nq-1 elementary reflectors, as returned by SSPTRD using packed
!> storage:
!>
!> if UPLO = 'U', Q = H(nq-1) . . . H(2) H(1);
!>
!> if UPLO = 'L', Q = H(1) H(2) . . . H(nq-1).
!> 

Parameters

SIDE

!>          SIDE is CHARACTER*1
!>          = 'L': apply Q or Q**T from the Left;
!>          = 'R': apply Q or Q**T from the Right.
!> 

UPLO

!>          UPLO is CHARACTER*1
!>          = 'U': Upper triangular packed storage used in previous
!>                 call to SSPTRD;
!>          = 'L': Lower triangular packed storage used in previous
!>                 call to SSPTRD.
!> 

TRANS

!>          TRANS is CHARACTER*1
!>          = 'N':  No transpose, apply Q;
!>          = 'T':  Transpose, apply Q**T.
!> 

M

!>          M is INTEGER
!>          The number of rows of the matrix C. M >= 0.
!> 

N

!>          N is INTEGER
!>          The number of columns of the matrix C. N >= 0.
!> 

AP

!>          AP is REAL array, dimension
!>                               (M*(M+1)/2) if SIDE = 'L'
!>                               (N*(N+1)/2) if SIDE = 'R'
!>          The vectors which define the elementary reflectors, as
!>          returned by SSPTRD.  AP is modified by the routine but
!>          restored on exit.
!> 

TAU

!>          TAU is REAL array, dimension (M-1) if SIDE = 'L'
!>                                     or (N-1) if SIDE = 'R'
!>          TAU(i) must contain the scalar factor of the elementary
!>          reflector H(i), as returned by SSPTRD.
!> 

C

!>          C is REAL 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

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

WORK

!>          WORK is REAL array, dimension
!>                                   (N) if SIDE = 'L'
!>                                   (M) if SIDE = 'R'
!> 

INFO

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

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 148 of file sopmtr.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Version 3.12.0 LAPACK