.TH "zlarfg.f" 3 "Wed Oct 15 2014" "Version 3.4.2" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME zlarfg.f \- .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBzlarfg\fP (N, ALPHA, X, INCX, TAU)" .br .RI "\fI\fBZLARFG\fP generates an elementary reflector (Householder matrix)\&. \fP" .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine zlarfg (integerN, complex*16ALPHA, complex*16, dimension( * )X, integerINCX, complex*16TAU)" .PP \fBZLARFG\fP generates an elementary reflector (Householder matrix)\&. .PP \fBPurpose: \fP .RS 4 .PP .nf ZLARFG generates a complex elementary reflector H of order n, such that H**H * ( alpha ) = ( beta ), H**H * H = I. ( x ) ( 0 ) where alpha and beta are scalars, with beta real, and x is an (n-1)-element complex vector. H is represented in the form H = I - tau * ( 1 ) * ( 1 v**H ) , ( v ) where tau is a complex scalar and v is a complex (n-1)-element vector. Note that H is not hermitian. If the elements of x are all zero and alpha is real, then tau = 0 and H is taken to be the unit matrix. Otherwise 1 <= real(tau) <= 2 and abs(tau-1) <= 1 . .fi .PP .RE .PP \fBParameters:\fP .RS 4 \fIN\fP .PP .nf N is INTEGER The order of the elementary reflector. .fi .PP .br \fIALPHA\fP .PP .nf ALPHA is COMPLEX*16 On entry, the value alpha. On exit, it is overwritten with the value beta. .fi .PP .br \fIX\fP .PP .nf X is COMPLEX*16 array, dimension (1+(N-2)*abs(INCX)) On entry, the vector x. On exit, it is overwritten with the vector v. .fi .PP .br \fIINCX\fP .PP .nf INCX is INTEGER The increment between elements of X. INCX > 0. .fi .PP .br \fITAU\fP .PP .nf TAU is COMPLEX*16 The value tau. .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 \fBDate:\fP .RS 4 September 2012 .RE .PP .PP Definition at line 107 of file zlarfg\&.f\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.