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DOUBLE PRECISION FUNCTION rexp(x)
C-----------------------------------------------------------------------
C EVALUATION OF THE FUNCTION EXP(X) - 1
C-----------------------------------------------------------------------
C .. Scalar Arguments ..
DOUBLE PRECISION x
C ..
C .. Local Scalars ..
DOUBLE PRECISION p1,p2,q1,q2,q3,q4,w
C ..
C .. Intrinsic Functions ..
INTRINSIC abs,exp
C ..
C .. Data statements ..
DATA p1/.914041914819518D-09/,p2/.238082361044469D-01/,
+ q1/-.499999999085958D+00/,q2/.107141568980644D+00/,
+ q3/-.119041179760821D-01/,q4/.595130811860248D-03/
C ..
C .. Executable Statements ..
C-----------------------
IF (abs(x).GT.0.15D0) GO TO 10
rexp = x* (((p2*x+p1)*x+1.0D0)/ ((((q4*x+q3)*x+q2)*x+q1)*x+1.0D0))
RETURN
C
10 w = exp(x)
IF (x.GT.0.0D0) GO TO 20
rexp = (w-0.5D0) - 0.5D0
RETURN
20 rexp = w* (0.5D0+ (0.5D0-1.0D0/w))
RETURN
END
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