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