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

version 1.7, 2010/12/21 13:53:38 version 1.8, 2011/07/22 07:38:11
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       SUBROUTINE DSPTRD( UPLO, N, AP, D, E, TAU, INFO )        SUBROUTINE DSPTRD( UPLO, N, AP, D, E, TAU, 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 ..
       CHARACTER          UPLO        CHARACTER          UPLO
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 *  *
 *  Each H(i) has the form  *  Each H(i) has the form
 *  *
 *     H(i) = I - tau * v * v'  *     H(i) = I - tau * v * v**T
 *  *
 *  where tau is a real scalar, and v is a real vector with  *  where tau is a real scalar, and v is a real vector with
 *  v(i+1:n) = 0 and v(i) = 1; v(1:i-1) is stored on exit in AP,  *  v(i+1:n) = 0 and v(i) = 1; v(1:i-1) is stored on exit in AP,
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 *  *
 *  Each H(i) has the form  *  Each H(i) has the form
 *  *
 *     H(i) = I - tau * v * v'  *     H(i) = I - tau * v * v**T
 *  *
 *  where tau is a real scalar, and v is a real vector with  *  where tau is a real scalar, and v is a real vector with
 *  v(1:i) = 0 and v(i+1) = 1; v(i+2:n) is stored on exit in AP,  *  v(1:i) = 0 and v(i+1) = 1; v(i+2:n) is stored on exit in AP,
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          I1 = N*( N-1 ) / 2 + 1           I1 = N*( N-1 ) / 2 + 1
          DO 10 I = N - 1, 1, -1           DO 10 I = N - 1, 1, -1
 *  *
 *           Generate elementary reflector H(i) = I - tau * v * v'  *           Generate elementary reflector H(i) = I - tau * v * v**T
 *           to annihilate A(1:i-1,i+1)  *           to annihilate A(1:i-1,i+1)
 *  *
             CALL DLARFG( I, AP( I1+I-1 ), AP( I1 ), 1, TAUI )              CALL DLARFG( I, AP( I1+I-1 ), AP( I1 ), 1, TAUI )
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                CALL DSPMV( UPLO, I, TAUI, AP, AP( I1 ), 1, ZERO, TAU,                 CALL DSPMV( UPLO, I, TAUI, AP, AP( I1 ), 1, ZERO, TAU,
      $                     1 )       $                     1 )
 *  *
 *              Compute  w := y - 1/2 * tau * (y'*v) * v  *              Compute  w := y - 1/2 * tau * (y**T *v) * v
 *  *
                ALPHA = -HALF*TAUI*DDOT( I, TAU, 1, AP( I1 ), 1 )                 ALPHA = -HALF*TAUI*DDOT( I, TAU, 1, AP( I1 ), 1 )
                CALL DAXPY( I, ALPHA, AP( I1 ), 1, TAU, 1 )                 CALL DAXPY( I, ALPHA, AP( I1 ), 1, TAU, 1 )
 *  *
 *              Apply the transformation as a rank-2 update:  *              Apply the transformation as a rank-2 update:
 *                 A := A - v * w' - w * v'  *                 A := A - v * w**T - w * v**T
 *  *
                CALL DSPR2( UPLO, I, -ONE, AP( I1 ), 1, TAU, 1, AP )                 CALL DSPR2( UPLO, I, -ONE, AP( I1 ), 1, TAU, 1, AP )
 *  *
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          DO 20 I = 1, N - 1           DO 20 I = 1, N - 1
             I1I1 = II + N - I + 1              I1I1 = II + N - I + 1
 *  *
 *           Generate elementary reflector H(i) = I - tau * v * v'  *           Generate elementary reflector H(i) = I - tau * v * v**T
 *           to annihilate A(i+2:n,i)  *           to annihilate A(i+2:n,i)
 *  *
             CALL DLARFG( N-I, AP( II+1 ), AP( II+2 ), 1, TAUI )              CALL DLARFG( N-I, AP( II+1 ), AP( II+2 ), 1, TAUI )
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                CALL DSPMV( UPLO, N-I, TAUI, AP( I1I1 ), AP( II+1 ), 1,                 CALL DSPMV( UPLO, N-I, TAUI, AP( I1I1 ), AP( II+1 ), 1,
      $                     ZERO, TAU( I ), 1 )       $                     ZERO, TAU( I ), 1 )
 *  *
 *              Compute  w := y - 1/2 * tau * (y'*v) * v  *              Compute  w := y - 1/2 * tau * (y**T *v) * v
 *  *
                ALPHA = -HALF*TAUI*DDOT( N-I, TAU( I ), 1, AP( II+1 ),                 ALPHA = -HALF*TAUI*DDOT( N-I, TAU( I ), 1, AP( II+1 ),
      $                 1 )       $                 1 )
                CALL DAXPY( N-I, ALPHA, AP( II+1 ), 1, TAU( I ), 1 )                 CALL DAXPY( N-I, ALPHA, AP( II+1 ), 1, TAU( I ), 1 )
 *  *
 *              Apply the transformation as a rank-2 update:  *              Apply the transformation as a rank-2 update:
 *                 A := A - v * w' - w * v'  *                 A := A - v * w**T - w * v**T
 *  *
                CALL DSPR2( UPLO, N-I, -ONE, AP( II+1 ), 1, TAU( I ), 1,                 CALL DSPR2( UPLO, N-I, -ONE, AP( II+1 ), 1, TAU( I ), 1,
      $                     AP( I1I1 ) )       $                     AP( I1I1 ) )
Removed from v.1.7  
changed lines
  Added in v.1.8

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