.TH "SRC/dlaeda.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
SRC/dlaeda.f
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBdlaeda\fP (n, tlvls, curlvl, curpbm, prmptr, perm, givptr, givcol, givnum, q, qptr, z, ztemp, info)"
.br
.RI "\fBDLAEDA\fP used by DSTEDC\&. Computes the Z vector determining the rank-one modification of the diagonal matrix\&. Used when the original matrix is dense\&. "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine dlaeda (integer n, integer tlvls, integer curlvl, integer curpbm, integer, dimension( * ) prmptr, integer, dimension( * ) perm, integer, dimension( * ) givptr, integer, dimension( 2, * ) givcol, double precision, dimension( 2, * ) givnum, double precision, dimension( * ) q, integer, dimension( * ) qptr, double precision, dimension( * ) z, double precision, dimension( * ) ztemp, integer info)"

.PP
\fBDLAEDA\fP used by DSTEDC\&. Computes the Z vector determining the rank-one modification of the diagonal matrix\&. Used when the original matrix is dense\&.  
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
!>
!> DLAEDA computes the Z vector corresponding to the merge step in the
!> CURLVLth step of the merge process with TLVLS steps for the CURPBMth
!> problem\&.
!> 
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
!>          N is INTEGER
!>         The dimension of the symmetric tridiagonal matrix\&.  N >= 0\&.
!> 
.fi
.PP
.br
\fITLVLS\fP 
.PP
.nf
!>          TLVLS is INTEGER
!>         The total number of merging levels in the overall divide and
!>         conquer tree\&.
!> 
.fi
.PP
.br
\fICURLVL\fP 
.PP
.nf
!>          CURLVL is INTEGER
!>         The current level in the overall merge routine,
!>         0 <= curlvl <= tlvls\&.
!> 
.fi
.PP
.br
\fICURPBM\fP 
.PP
.nf
!>          CURPBM is INTEGER
!>         The current problem in the current level in the overall
!>         merge routine (counting from upper left to lower right)\&.
!> 
.fi
.PP
.br
\fIPRMPTR\fP 
.PP
.nf
!>          PRMPTR is INTEGER array, dimension (N lg N)
!>         Contains a list of pointers which indicate where in PERM a
!>         level's permutation is stored\&.  PRMPTR(i+1) - PRMPTR(i)
!>         indicates the size of the permutation and incidentally the
!>         size of the full, non-deflated problem\&.
!> 
.fi
.PP
.br
\fIPERM\fP 
.PP
.nf
!>          PERM is INTEGER array, dimension (N lg N)
!>         Contains the permutations (from deflation and sorting) to be
!>         applied to each eigenblock\&.
!> 
.fi
.PP
.br
\fIGIVPTR\fP 
.PP
.nf
!>          GIVPTR is INTEGER array, dimension (N lg N)
!>         Contains a list of pointers which indicate where in GIVCOL a
!>         level's Givens rotations are stored\&.  GIVPTR(i+1) - GIVPTR(i)
!>         indicates the number of Givens rotations\&.
!> 
.fi
.PP
.br
\fIGIVCOL\fP 
.PP
.nf
!>          GIVCOL is INTEGER array, dimension (2, N lg N)
!>         Each pair of numbers indicates a pair of columns to take place
!>         in a Givens rotation\&.
!> 
.fi
.PP
.br
\fIGIVNUM\fP 
.PP
.nf
!>          GIVNUM is DOUBLE PRECISION array, dimension (2, N lg N)
!>         Each number indicates the S value to be used in the
!>         corresponding Givens rotation\&.
!> 
.fi
.PP
.br
\fIQ\fP 
.PP
.nf
!>          Q is DOUBLE PRECISION array, dimension (N**2)
!>         Contains the square eigenblocks from previous levels, the
!>         starting positions for blocks are given by QPTR\&.
!> 
.fi
.PP
.br
\fIQPTR\fP 
.PP
.nf
!>          QPTR is INTEGER array, dimension (N+2)
!>         Contains a list of pointers which indicate where in Q an
!>         eigenblock is stored\&.  SQRT( QPTR(i+1) - QPTR(i) ) indicates
!>         the size of the block\&.
!> 
.fi
.PP
.br
\fIZ\fP 
.PP
.nf
!>          Z is DOUBLE PRECISION array, dimension (N)
!>         On output this vector contains the updating vector (the last
!>         row of the first sub-eigenvector matrix and the first row of
!>         the second sub-eigenvector matrix)\&.
!> 
.fi
.PP
.br
\fIZTEMP\fP 
.PP
.nf
!>          ZTEMP is DOUBLE PRECISION array, dimension (N)
!> 
.fi
.PP
.br
\fIINFO\fP 
.PP
.nf
!>          INFO is INTEGER
!>          = 0:  successful exit\&.
!>          < 0:  if INFO = -i, the i-th argument had an illegal value\&.
!> 
.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
Jeff Rutter, Computer Science Division, University of California at Berkeley, USA 
.RE
.PP

.PP
Definition at line \fB164\fP of file \fBdlaeda\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.