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REAL FUNCTION SASUM(N,SX,INCX)
* .. Scalar Arguments ..
INTEGER INCX,N
* ..
* .. Array Arguments ..
REAL SX(*)
* ..
*
* Purpose
* =======
*
* takes the sum of the absolute values.
* uses unrolled loops for increment equal to one.
* 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 ..
REAL STEMP
INTEGER I,M,MP1,NINCX
* ..
* .. Intrinsic Functions ..
INTRINSIC ABS,MOD
* ..
SASUM = 0.0e0
STEMP = 0.0e0
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
STEMP = STEMP + ABS(SX(I))
10 CONTINUE
SASUM = STEMP
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
STEMP = STEMP + ABS(SX(I))
30 CONTINUE
IF (N.LT.6) GO TO 60
40 MP1 = M + 1
DO 50 I = MP1,N,6
STEMP = STEMP + ABS(SX(I)) + ABS(SX(I+1)) + ABS(SX(I+2)) +
+ ABS(SX(I+3)) + ABS(SX(I+4)) + ABS(SX(I+5))
50 CONTINUE
60 SASUM = STEMP
RETURN
END
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