[BACK]Return to dpttrf.f CVS log [TXT] [DIR] Up to [local] / rpl / lapack / lapack

Diff for /rpl/lapack/lapack/dpttrf.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
Line 1 Line 1
       SUBROUTINE DPTTRF( N, D, E, INFO )        SUBROUTINE DPTTRF( N, D, E, INFO )
 *  *
 *  -- 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            INFO, N        INTEGER            INFO, N
Line 15 Line 15
 *  Purpose  *  Purpose
 *  =======  *  =======
 *  *
 *  DPTTRF computes the L*D*L' factorization of a real symmetric  *  DPTTRF computes the L*D*L**T factorization of a real symmetric
 *  positive definite tridiagonal matrix A.  The factorization may also  *  positive definite tridiagonal matrix A.  The factorization may also
 *  be regarded as having the form A = U'*D*U.  *  be regarded as having the form A = U**T*D*U.
 *  *
 *  Arguments  *  Arguments
 *  =========  *  =========
Line 28 Line 28
 *  D       (input/output) DOUBLE PRECISION array, dimension (N)  *  D       (input/output) DOUBLE PRECISION array, dimension (N)
 *          On entry, the n diagonal elements of the tridiagonal matrix  *          On entry, the n diagonal elements of the tridiagonal matrix
 *          A.  On exit, the n diagonal elements of the diagonal matrix  *          A.  On exit, the n diagonal elements of the diagonal matrix
 *          D from the L*D*L' factorization of A.  *          D from the L*D*L**T factorization of A.
 *  *
 *  E       (input/output) DOUBLE PRECISION array, dimension (N-1)  *  E       (input/output) DOUBLE PRECISION array, dimension (N-1)
 *          On entry, the (n-1) subdiagonal elements of the tridiagonal  *          On entry, the (n-1) subdiagonal elements of the tridiagonal
 *          matrix A.  On exit, the (n-1) subdiagonal elements of the  *          matrix A.  On exit, the (n-1) subdiagonal elements of the
 *          unit bidiagonal factor L from the L*D*L' factorization of A.  *          unit bidiagonal factor L from the L*D*L**T factorization of A.
 *          E can also be regarded as the superdiagonal of the unit  *          E can also be regarded as the superdiagonal of the unit
 *          bidiagonal factor U from the U'*D*U factorization of A.  *          bidiagonal factor U from the U**T*D*U factorization of A.
 *  *
 *  INFO    (output) INTEGER  *  INFO    (output) INTEGER
 *          = 0: successful exit  *          = 0: successful exit
Line 77 Line 77
       IF( N.EQ.0 )        IF( N.EQ.0 )
      $   RETURN       $   RETURN
 *  *
 *     Compute the L*D*L' (or U'*D*U) factorization of A.  *     Compute the L*D*L**T (or U**T*D*U) factorization of A.
 *  *
       I4 = MOD( N-1, 4 )        I4 = MOD( N-1, 4 )
       DO 10 I = 1, I4        DO 10 I = 1, I4
Removed from v.1.7  
changed lines
  Added in v.1.8

CVSweb interface <joel.bertrand@systella.fr>