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authorjulie <julielangou@users.noreply.github.com>2011-10-06 06:53:11 +0000
committerjulie <julielangou@users.noreply.github.com>2011-10-06 06:53:11 +0000
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- SUBROUTINE DGTTRF( N, DL, D, DU, DU2, IPIV, INFO )
-*
-* -- LAPACK routine (version 3.2) --
-* -- LAPACK is a software package provided by Univ. of Tennessee, --
-* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
-* November 2006
-*
-* .. Scalar Arguments ..
- INTEGER INFO, N
-* ..
-* .. Array Arguments ..
- INTEGER IPIV( * )
- DOUBLE PRECISION D( * ), DL( * ), DU( * ), DU2( * )
-* ..
-*
+*> \brief \b DGTTRF
+*
+* =========== DOCUMENTATION ===========
+*
+* Online html documentation available at
+* http://www.netlib.org/lapack/explore-html/
+*
+* Definition
+* ==========
+*
+* SUBROUTINE DGTTRF( N, DL, D, DU, DU2, IPIV, INFO )
+*
+* .. Scalar Arguments ..
+* INTEGER INFO, N
+* ..
+* .. Array Arguments ..
+* INTEGER IPIV( * )
+* DOUBLE PRECISION D( * ), DL( * ), DU( * ), DU2( * )
+* ..
+*
* Purpose
* =======
*
-* DGTTRF computes an LU factorization of a real tridiagonal matrix A
-* using elimination with partial pivoting and row interchanges.
-*
-* The factorization has the form
-* A = L * U
-* where L is a product of permutation and unit lower bidiagonal
-* matrices and U is upper triangular with nonzeros in only the main
-* diagonal and first two superdiagonals.
+*>\details \b Purpose:
+*>\verbatim
+*>
+*> DGTTRF computes an LU factorization of a real tridiagonal matrix A
+*> using elimination with partial pivoting and row interchanges.
+*>
+*> The factorization has the form
+*> A = L * U
+*> where L is a product of permutation and unit lower bidiagonal
+*> matrices and U is upper triangular with nonzeros in only the main
+*> diagonal and first two superdiagonals.
+*>
+*>\endverbatim
*
* Arguments
* =========
*
-* N (input) INTEGER
-* The order of the matrix A.
-*
-* DL (input/output) DOUBLE PRECISION array, dimension (N-1)
-* On entry, DL must contain the (n-1) sub-diagonal elements of
-* A.
-*
-* On exit, DL is overwritten by the (n-1) multipliers that
-* define the matrix L from the LU factorization of A.
-*
-* D (input/output) DOUBLE PRECISION array, dimension (N)
-* On entry, D must contain the diagonal elements of A.
+*> \param[in] N
+*> \verbatim
+*> N is INTEGER
+*> The order of the matrix A.
+*> \endverbatim
+*>
+*> \param[in,out] DL
+*> \verbatim
+*> DL is DOUBLE PRECISION array, dimension (N-1)
+*> On entry, DL must contain the (n-1) sub-diagonal elements of
+*> A.
+*> \endverbatim
+*> \verbatim
+*> On exit, DL is overwritten by the (n-1) multipliers that
+*> define the matrix L from the LU factorization of A.
+*> \endverbatim
+*>
+*> \param[in,out] D
+*> \verbatim
+*> D is DOUBLE PRECISION array, dimension (N)
+*> On entry, D must contain the diagonal elements of A.
+*> \endverbatim
+*> \verbatim
+*> On exit, D is overwritten by the n diagonal elements of the
+*> upper triangular matrix U from the LU factorization of A.
+*> \endverbatim
+*>
+*> \param[in,out] DU
+*> \verbatim
+*> DU is DOUBLE PRECISION array, dimension (N-1)
+*> On entry, DU must contain the (n-1) super-diagonal elements
+*> of A.
+*> \endverbatim
+*> \verbatim
+*> On exit, DU is overwritten by the (n-1) elements of the first
+*> super-diagonal of U.
+*> \endverbatim
+*>
+*> \param[out] DU2
+*> \verbatim
+*> DU2 is DOUBLE PRECISION array, dimension (N-2)
+*> On exit, DU2 is overwritten by the (n-2) elements of the
+*> second super-diagonal of U.
+*> \endverbatim
+*>
+*> \param[out] IPIV
+*> \verbatim
+*> 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.
+*> \endverbatim
+*>
+*> \param[out] INFO
+*> \verbatim
+*> INFO is INTEGER
+*> = 0: successful exit
+*> < 0: if INFO = -k, the k-th argument had an illegal value
+*> > 0: if INFO = k, U(k,k) is exactly zero. The factorization
+*> has been completed, but the factor U is exactly
+*> singular, and division by zero will occur if it is used
+*> to solve a system of equations.
+*> \endverbatim
+*>
+*
+* Authors
+* =======
*
-* On exit, D is overwritten by the n diagonal elements of the
-* upper triangular matrix U from the LU factorization of A.
+*> \author Univ. of Tennessee
+*> \author Univ. of California Berkeley
+*> \author Univ. of Colorado Denver
+*> \author NAG Ltd.
*
-* DU (input/output) DOUBLE PRECISION array, dimension (N-1)
-* On entry, DU must contain the (n-1) super-diagonal elements
-* of A.
+*> \date November 2011
*
-* On exit, DU is overwritten by the (n-1) elements of the first
-* super-diagonal of U.
+*> \ingroup doubleOTHERcomputational
*
-* DU2 (output) DOUBLE PRECISION array, dimension (N-2)
-* On exit, DU2 is overwritten by the (n-2) elements of the
-* second super-diagonal of U.
+* =====================================================================
+ SUBROUTINE DGTTRF( N, DL, D, DU, DU2, IPIV, INFO )
*
-* IPIV (output) 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.
+* -- LAPACK computational routine (version 3.2) --
+* -- LAPACK is a software package provided by Univ. of Tennessee, --
+* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
+* November 2011
*
-* INFO (output) INTEGER
-* = 0: successful exit
-* < 0: if INFO = -k, the k-th argument had an illegal value
-* > 0: if INFO = k, U(k,k) is exactly zero. The factorization
-* has been completed, but the factor U is exactly
-* singular, and division by zero will occur if it is used
-* to solve a system of equations.
+* .. Scalar Arguments ..
+ INTEGER INFO, N
+* ..
+* .. Array Arguments ..
+ INTEGER IPIV( * )
+ DOUBLE PRECISION D( * ), DL( * ), DU( * ), DU2( * )
+* ..
*
* =====================================================================
*