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Diff for /rpl/lapack/lapack/dlasd4.f between versions 1.14 and 1.15

version 1.14, 2012/12/14 14:22:35 version 1.15, 2014/01/27 09:24:34
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 *> \author Univ. of Colorado Denver  *> \author Univ. of Colorado Denver
 *> \author NAG Ltd.  *> \author NAG Ltd.
 *  *
 *> \date September 2012  *> \date November 2013
 *  *
 *> \ingroup auxOTHERauxiliary  *> \ingroup auxOTHERauxiliary
 *  *
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 *  =====================================================================  *  =====================================================================
       SUBROUTINE DLASD4( N, I, D, Z, DELTA, RHO, SIGMA, WORK, INFO )        SUBROUTINE DLASD4( N, I, D, Z, DELTA, RHO, SIGMA, WORK, INFO )
 *  *
 *  -- LAPACK auxiliary routine (version 3.4.2) --  *  -- LAPACK auxiliary routine (version 3.5.0) --
 *  -- 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..--
 *     September 2012  *     November 2013
 *  *
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       INTEGER            I, INFO, N        INTEGER            I, INFO, N
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 *  *
       EPS = DLAMCH( 'Epsilon' )        EPS = DLAMCH( 'Epsilon' )
       RHOINV = ONE / RHO        RHOINV = ONE / RHO
         TAU2= ZERO
 *  *
 *     The case I = N  *     The case I = N
 *  *
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                ELSE                 ELSE
                   TAU2 = ( A+SQRT( A*A+FOUR*B*C ) ) / ( TWO*C )                    TAU2 = ( A+SQRT( A*A+FOUR*B*C ) ) / ( TWO*C )
                END IF                 END IF
                  TAU = TAU2 / ( D( N )+SQRT( D( N )*D( N )+TAU2 ) )
             END IF              END IF
 *  *
 *           It can be proved that  *           It can be proved that
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             ELSE              ELSE
                TAU2 = ( A+SQRT( A*A+FOUR*B*C ) ) / ( TWO*C )                 TAU2 = ( A+SQRT( A*A+FOUR*B*C ) ) / ( TWO*C )
             END IF              END IF
               TAU = TAU2 / ( D( N )+SQRT( D( N )*D( N )+TAU2 ) )
   
 *  *
 *           It can be proved that  *           It can be proved that
 *           D(N)^2 < D(N)^2+TAU2 < SIGMA(N)^2 < D(N)^2+RHO/2  *           D(N)^2 < D(N)^2+TAU2 < SIGMA(N)^2 < D(N)^2+RHO/2
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 *  *
 *        The following TAU is to approximate SIGMA_n - D( N )  *        The following TAU is to approximate SIGMA_n - D( N )
 *  *
          TAU = TAU2 / ( D( N )+SQRT( D( N )*D( N )+TAU2 ) )  *         TAU = TAU2 / ( D( N )+SQRT( D( N )*D( N )+TAU2 ) )
 *  *
          SIGMA = D( N ) + TAU           SIGMA = D( N ) + TAU
          DO 30 J = 1, N           DO 30 J = 1, N
Removed from v.1.14  
changed lines
  Added in v.1.15

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