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      DOUBLE PRECISION FUNCTION DASUM(N,DX,INCX)
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*     .. Scalar Arguments ..
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      INTEGER INCX,N
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*     ..
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*     .. Array Arguments ..
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      DOUBLE PRECISION DX(*)
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*     ..
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*
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*  Purpose
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*  =======
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*
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*     takes the sum of the absolute values.
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*     jack dongarra, linpack, 3/11/78.
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*     modified 3/93 to return if incx .le. 0.
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*     modified 12/3/93, array(1) declarations changed to array(*)
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*
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*
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*     .. Local Scalars ..
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      DOUBLE PRECISION DTEMP
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      INTEGER I,M,MP1,NINCX
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*     ..
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*     .. Intrinsic Functions ..
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      INTRINSIC DABS,MOD
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*     ..
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      DASUM = 0.0d0
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      DTEMP = 0.0d0
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      IF (N.LE.0 .OR. INCX.LE.0) RETURN
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      IF (INCX.EQ.1) GO TO 20
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*
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*        code for increment not equal to 1
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*
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      NINCX = N*INCX
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      DO 10 I = 1,NINCX,INCX
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          DTEMP = DTEMP + DABS(DX(I))
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   10 CONTINUE
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      DASUM = DTEMP
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      RETURN
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*
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*        code for increment equal to 1
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*
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*
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*        clean-up loop
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*
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   20 M = MOD(N,6)
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      IF (M.EQ.0) GO TO 40
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      DO 30 I = 1,M
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          DTEMP = DTEMP + DABS(DX(I))
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   30 CONTINUE
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      IF (N.LT.6) GO TO 60
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   40 MP1 = M + 1
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      DO 50 I = MP1,N,6
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          DTEMP = DTEMP + DABS(DX(I)) + DABS(DX(I+1)) + DABS(DX(I+2)) +
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     +            DABS(DX(I+3)) + DABS(DX(I+4)) + DABS(DX(I+5))
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   50 CONTINUE
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   60 DASUM = DTEMP
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      RETURN
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      END