.TH "SRC/dlarz.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME SRC/dlarz.f .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBdlarz\fP (side, m, n, l, v, incv, tau, c, ldc, work)" .br .RI "\fBDLARZ\fP applies an elementary reflector (as returned by stzrzf) to a general matrix\&. " .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine dlarz (character side, integer m, integer n, integer l, double precision, dimension( * ) v, integer incv, double precision tau, double precision, dimension( ldc, * ) c, integer ldc, double precision, dimension( * ) work)" .PP \fBDLARZ\fP applies an elementary reflector (as returned by stzrzf) to a general matrix\&. .PP \fBPurpose:\fP .RS 4 .PP .nf !> !> DLARZ applies a real elementary reflector H to a real M-by-N !> matrix C, from either the left or the right\&. H is represented in the !> form !> !> H = I - tau * v * v**T !> !> where tau is a real scalar and v is a real vector\&. !> !> If tau = 0, then H is taken to be the unit matrix\&. !> !> !> H is a product of k elementary reflectors as returned by DTZRZF\&. !> .fi .PP .RE .PP \fBParameters\fP .RS 4 \fISIDE\fP .PP .nf !> SIDE is CHARACTER*1 !> = 'L': form H * C !> = 'R': form C * H !> .fi .PP .br \fIM\fP .PP .nf !> M is INTEGER !> The number of rows of the matrix C\&. !> .fi .PP .br \fIN\fP .PP .nf !> N is INTEGER !> The number of columns of the matrix C\&. !> .fi .PP .br \fIL\fP .PP .nf !> L is INTEGER !> The number of entries of the vector V containing !> the meaningful part of the Householder vectors\&. !> If SIDE = 'L', M >= L >= 0, if SIDE = 'R', N >= L >= 0\&. !> .fi .PP .br \fIV\fP .PP .nf !> V is DOUBLE PRECISION array, dimension (1+(L-1)*abs(INCV)) !> The vector v in the representation of H as returned by !> DTZRZF\&. V is not used if TAU = 0\&. !> .fi .PP .br \fIINCV\fP .PP .nf !> INCV is INTEGER !> The increment between elements of v\&. INCV <> 0\&. !> .fi .PP .br \fITAU\fP .PP .nf !> TAU is DOUBLE PRECISION !> The value tau in the representation of H\&. !> .fi .PP .br \fIC\fP .PP .nf !> C is DOUBLE PRECISION array, dimension (LDC,N) !> On entry, the M-by-N matrix C\&. !> On exit, C is overwritten by the matrix H * C if SIDE = 'L', !> or C * H if SIDE = 'R'\&. !> .fi .PP .br \fILDC\fP .PP .nf !> LDC is INTEGER !> The leading dimension of the array C\&. LDC >= max(1,M)\&. !> .fi .PP .br \fIWORK\fP .PP .nf !> WORK is DOUBLE PRECISION array, dimension !> (N) if SIDE = 'L' !> or (M) if SIDE = 'R' !> .fi .PP .RE .PP \fBAuthor\fP .RS 4 Univ\&. of Tennessee .PP Univ\&. of California Berkeley .PP Univ\&. of Colorado Denver .PP NAG Ltd\&. .RE .PP \fBContributors:\fP .RS 4 A\&. Petitet, Computer Science Dept\&., Univ\&. of Tenn\&., Knoxville, USA .RE .PP \fBFurther Details:\fP .RS 4 .PP .nf !> .fi .PP .RE .PP .PP Definition at line \fB144\fP of file \fBdlarz\&.f\fP\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.