.TH "SRC/dlaed5.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*-
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.SH NAME
SRC/dlaed5.f
.SH SYNOPSIS
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.SS "Functions/Subroutines"

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.ti -1c
.RI "subroutine \fBdlaed5\fP (i, d, z, delta, rho, dlam)"
.br
.RI "\fBDLAED5\fP used by DSTEDC\&. Solves the 2-by-2 secular equation\&. "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine dlaed5 (integer i, double precision, dimension( 2 ) d, double precision, dimension( 2 ) z, double precision, dimension( 2 ) delta, double precision rho, double precision dlam)"

.PP
\fBDLAED5\fP used by DSTEDC\&. Solves the 2-by-2 secular equation\&.  
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\fBPurpose:\fP
.RS 4

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.nf
 This subroutine computes the I-th eigenvalue of a symmetric rank-one
 modification of a 2-by-2 diagonal matrix

            diag( D )  +  RHO * Z * transpose(Z) \&.

 The diagonal elements in the array D are assumed to satisfy

            D(i) < D(j)  for  i < j \&.

 We also assume RHO > 0 and that the Euclidean norm of the vector
 Z is one\&.
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.RE
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\fBParameters\fP
.RS 4
\fII\fP 
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          I is INTEGER
         The index of the eigenvalue to be computed\&.  I = 1 or I = 2\&.
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\fID\fP 
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          D is DOUBLE PRECISION array, dimension (2)
         The original eigenvalues\&.  We assume D(1) < D(2)\&.
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\fIZ\fP 
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          Z is DOUBLE PRECISION array, dimension (2)
         The components of the updating vector\&.
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\fIDELTA\fP 
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          DELTA is DOUBLE PRECISION array, dimension (2)
         The vector DELTA contains the information necessary
         to construct the eigenvectors\&.
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\fIRHO\fP 
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          RHO is DOUBLE PRECISION
         The scalar in the symmetric updating formula\&.
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\fIDLAM\fP 
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          DLAM is DOUBLE PRECISION
         The computed lambda_I, the I-th updated eigenvalue\&.
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.RE
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\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
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Univ\&. of California Berkeley 
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Univ\&. of Colorado Denver 
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NAG Ltd\&. 
.RE
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\fBContributors:\fP
.RS 4
Ren-Cang Li, Computer Science Division, University of California at Berkeley, USA 
.RE
.PP

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Definition at line \fB107\fP of file \fBdlaed5\&.f\fP\&.
.SH "Author"
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Generated automatically by Doxygen for LAPACK from the source code\&.