.TH "TESTING/LIN/dgtt01.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
TESTING/LIN/dgtt01.f
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBdgtt01\fP (n, dl, d, du, dlf, df, duf, du2, ipiv, work, ldwork, rwork, resid)"
.br
.RI "\fBDGTT01\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine dgtt01 (integer n, double precision, dimension( * ) dl, double precision, dimension( * ) d, double precision, dimension( * ) du, double precision, dimension( * ) dlf, double precision, dimension( * ) df, double precision, dimension( * ) duf, double precision, dimension( * ) du2, integer, dimension( * ) ipiv, double precision, dimension( ldwork, * ) work, integer ldwork, double precision, dimension( * ) rwork, double precision resid)"

.PP
\fBDGTT01\fP 
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\fBPurpose:\fP
.RS 4

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.nf
 DGTT01 reconstructs a tridiagonal matrix A from its LU factorization
 and computes the residual
    norm(L*U - A) / ( norm(A) * EPS ),
 where EPS is the machine epsilon\&.
.fi
.PP
 
.RE
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\fBParameters\fP
.RS 4
\fIN\fP 
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.nf
          N is INTEGER
          The order of the matrix A\&.  N >= 0\&.
.fi
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.br
\fIDL\fP 
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          DL is DOUBLE PRECISION array, dimension (N-1)
          The (n-1) sub-diagonal elements of A\&.
.fi
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\fID\fP 
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          D is DOUBLE PRECISION array, dimension (N)
          The diagonal elements of A\&.
.fi
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.br
\fIDU\fP 
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.nf
          DU is DOUBLE PRECISION array, dimension (N-1)
          The (n-1) super-diagonal elements of A\&.
.fi
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\fIDLF\fP 
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          DLF is DOUBLE PRECISION array, dimension (N-1)
          The (n-1) multipliers that define the matrix L from the
          LU factorization of A\&.
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\fIDF\fP 
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          DF is DOUBLE PRECISION array, dimension (N)
          The n diagonal elements of the upper triangular matrix U from
          the LU factorization of A\&.
.fi
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.br
\fIDUF\fP 
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.nf
          DUF is DOUBLE PRECISION array, dimension (N-1)
          The (n-1) elements of the first super-diagonal of U\&.
.fi
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\fIDU2\fP 
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          DU2 is DOUBLE PRECISION array, dimension (N-2)
          The (n-2) elements of the second super-diagonal of U\&.
.fi
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\fIIPIV\fP 
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          IPIV is INTEGER array, dimension (N)
          The pivot indices; for 1 <= i <= n, row i of the matrix was
          interchanged with row IPIV(i)\&.  IPIV(i) will always be either
          i or i+1; IPIV(i) = i indicates a row interchange was not
          required\&.
.fi
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.br
\fIWORK\fP 
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          WORK is DOUBLE PRECISION array, dimension (LDWORK,N)
.fi
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\fILDWORK\fP 
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          LDWORK is INTEGER
          The leading dimension of the array WORK\&.  LDWORK >= max(1,N)\&.
.fi
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.br
\fIRWORK\fP 
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          RWORK is DOUBLE PRECISION array, dimension (N)
.fi
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.br
\fIRESID\fP 
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          RESID is DOUBLE PRECISION
          The scaled residual:  norm(L*U - A) / (norm(A) * EPS)
.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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Definition at line \fB132\fP of file \fBdgtt01\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.