.TH "claqr1.f" 3 "Sun May 26 2013" "Version 3.4.1" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
claqr1.f \- 
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBclaqr1\fP (N, H, LDH, S1, S2, V)"
.br
.RI "\fI\fBCLAQR1\fP \fP"
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine claqr1 (integerN, complex, dimension( ldh, * )H, integerLDH, complexS1, complexS2, complex, dimension( * )V)"

.PP
\fBCLAQR1\fP  
.PP
\fBPurpose: \fP
.RS 4

.PP
.nf
      Given a 2-by-2 or 3-by-3 matrix H, CLAQR1 sets v to a
      scalar multiple of the first column of the product

      (*)  K = (H - s1*I)*(H - s2*I)

      scaling to avoid overflows and most underflows.

      This is useful for starting double implicit shift bulges
      in the QR algorithm.
.fi
.PP
 
.RE
.PP
\fBParameters:\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is integer
              Order of the matrix H. N must be either 2 or 3.
.fi
.PP
.br
\fIH\fP 
.PP
.nf
          H is COMPLEX array of dimension (LDH,N)
              The 2-by-2 or 3-by-3 matrix H in (*).
.fi
.PP
.br
\fILDH\fP 
.PP
.nf
          LDH is integer
              The leading dimension of H as declared in
              the calling procedure.  LDH.GE.N
.fi
.PP
.br
\fIS1\fP 
.PP
.nf
          S1 is COMPLEX
.fi
.PP
.br
\fIS2\fP 
.PP
.nf
          S2 is COMPLEX

          S1 and S2 are the shifts defining K in (*) above.
.fi
.PP
.br
\fIV\fP 
.PP
.nf
          V is COMPLEX array of dimension N
              A scalar multiple of the first column of the
              matrix K in (*).
.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
November 2011 
.RE
.PP
\fBContributors: \fP
.RS 4
Karen Braman and Ralph Byers, Department of Mathematics, University of Kansas, USA 
.RE
.PP

.PP
Definition at line 108 of file claqr1\&.f\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.