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Diff for /rpl/lapack/lapack/dptts2.f between versions 1.7 and 1.8

version 1.7, 2010/12/21 13:53:37 version 1.8, 2011/07/22 07:38:10
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       SUBROUTINE DPTTS2( N, NRHS, D, E, B, LDB )        SUBROUTINE DPTTS2( N, NRHS, D, E, B, LDB )
 *  *
 *  -- LAPACK routine (version 3.2) --  *  -- LAPACK routine (version 3.3.1) --
 *  -- LAPACK is a software package provided by Univ. of Tennessee,    --  *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
 *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--  *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
 *     November 2006  *  -- April 2011                                                      --
 *  *
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       INTEGER            LDB, N, NRHS        INTEGER            LDB, N, NRHS
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 *  *
 *  DPTTS2 solves a tridiagonal system of the form  *  DPTTS2 solves a tridiagonal system of the form
 *     A * X = B  *     A * X = B
 *  using the L*D*L' factorization of A computed by DPTTRF.  D is a  *  using the L*D*L**T factorization of A computed by DPTTRF.  D is a
 *  diagonal matrix specified in the vector D, L is a unit bidiagonal  *  diagonal matrix specified in the vector D, L is a unit bidiagonal
 *  matrix whose subdiagonal is specified in the vector E, and X and B  *  matrix whose subdiagonal is specified in the vector E, and X and B
 *  are N by NRHS matrices.  *  are N by NRHS matrices.
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 *  *
 *  D       (input) DOUBLE PRECISION array, dimension (N)  *  D       (input) DOUBLE PRECISION array, dimension (N)
 *          The n diagonal elements of the diagonal matrix D from the  *          The n diagonal elements of the diagonal matrix D from the
 *          L*D*L' factorization of A.  *          L*D*L**T factorization of A.
 *  *
 *  E       (input) DOUBLE PRECISION array, dimension (N-1)  *  E       (input) DOUBLE PRECISION array, dimension (N-1)
 *          The (n-1) subdiagonal elements of the unit bidiagonal factor  *          The (n-1) subdiagonal elements of the unit bidiagonal factor
 *          L from the L*D*L' factorization of A.  E can also be regarded  *          L from the L*D*L**T factorization of A.  E can also be regarded
 *          as the superdiagonal of the unit bidiagonal factor U from the  *          as the superdiagonal of the unit bidiagonal factor U from the
 *          factorization A = U'*D*U.  *          factorization A = U**T*D*U.
 *  *
 *  B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)  *  B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)
 *          On entry, the right hand side vectors B for the system of  *          On entry, the right hand side vectors B for the system of
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          RETURN           RETURN
       END IF        END IF
 *  *
 *     Solve A * X = B using the factorization A = L*D*L',  *     Solve A * X = B using the factorization A = L*D*L**T,
 *     overwriting each right hand side vector with its solution.  *     overwriting each right hand side vector with its solution.
 *  *
       DO 30 J = 1, NRHS        DO 30 J = 1, NRHS
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             B( I, J ) = B( I, J ) - B( I-1, J )*E( I-1 )              B( I, J ) = B( I, J ) - B( I-1, J )*E( I-1 )
    10    CONTINUE     10    CONTINUE
 *  *
 *           Solve D * L' * x = b.  *           Solve D * L**T * x = b.
 *  *
          B( N, J ) = B( N, J ) / D( N )           B( N, J ) = B( N, J ) / D( N )
          DO 20 I = N - 1, 1, -1           DO 20 I = N - 1, 1, -1
Removed from v.1.7  
changed lines
  Added in v.1.8

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