.TH "cheequb.f" 3 "Tue Nov 14 2017" "Version 3.8.0" "LAPACK" \" -*- nroff -*-
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.SH NAME
cheequb.f
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

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.ti -1c
.RI "subroutine \fBcheequb\fP (UPLO, \fBN\fP, A, \fBLDA\fP, S, SCOND, AMAX, WORK, INFO)"
.br
.RI "\fBCHEEQUB\fP "
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.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine cheequb (character UPLO, integer N, complex, dimension( lda, * ) A, integer LDA, real, dimension( * ) S, real SCOND, real AMAX, complex, dimension( * ) WORK, integer INFO)"

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\fBCHEEQUB\fP  
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\fBPurpose: \fP
.RS 4

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.nf
 CHEEQUB computes row and column scalings intended to equilibrate a
 Hermitian matrix A (with respect to the Euclidean norm) and reduce
 its condition number. The scale factors S are computed by the BIN
 algorithm (see references) so that the scaled matrix B with elements
 B(i,j) = S(i)*A(i,j)*S(j) has a condition number within a factor N of
 the smallest possible condition number over all possible diagonal
 scalings.
.fi
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.RE
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\fBParameters:\fP
.RS 4
\fIUPLO\fP 
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          UPLO is CHARACTER*1
          = 'U':  Upper triangle of A is stored;
          = 'L':  Lower triangle of A is stored.
.fi
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\fIN\fP 
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          N is INTEGER
          The order of the matrix A. N >= 0.
.fi
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\fIA\fP 
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          A is COMPLEX array, dimension (LDA,N)
          The N-by-N Hermitian matrix whose scaling factors are to be
          computed.
.fi
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\fILDA\fP 
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          LDA is INTEGER
          The leading dimension of the array A. LDA >= max(1,N).
.fi
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\fIS\fP 
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          S is REAL array, dimension (N)
          If INFO = 0, S contains the scale factors for A.
.fi
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\fISCOND\fP 
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          SCOND is REAL
          If INFO = 0, S contains the ratio of the smallest S(i) to
          the largest S(i). If SCOND >= 0.1 and AMAX is neither too
          large nor too small, it is not worth scaling by S.
.fi
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\fIAMAX\fP 
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          AMAX is REAL
          Largest absolute value of any matrix element. If AMAX is
          very close to overflow or very close to underflow, the
          matrix should be scaled.
.fi
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\fIWORK\fP 
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          WORK is COMPLEX array, dimension (2*N)
.fi
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\fIINFO\fP 
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          INFO is INTEGER
          = 0:  successful exit
          < 0:  if INFO = -i, the i-th argument had an illegal value
          > 0:  if INFO = i, the i-th diagonal element is nonpositive.
.fi
.PP
 
.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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\fBDate:\fP
.RS 4
April 2012 
.RE
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\fBReferences: \fP
.RS 4
Livne, O\&.E\&. and Golub, G\&.H\&., 'Scaling by Binormalization', 
.br
 Numerical Algorithms, vol\&. 35, no\&. 1, pp\&. 97-120, January 2004\&. 
.br
 DOI 10\&.1023/B:NUMA\&.0000016606\&.32820\&.69 
.br
 Tech report version: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.3.1679 
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Definition at line 134 of file cheequb\&.f\&.
.SH "Author"
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Generated automatically by Doxygen for LAPACK from the source code\&.
