*DECK DF1P
      DOUBLE PRECISION FUNCTION DF1P (X)
C***BEGIN PROLOGUE  DF1P
C***PURPOSE  Subsidiary to
C***LIBRARY   SLATEC
C***AUTHOR  (UNKNOWN)
C***ROUTINES CALLED  (NONE)
C***REVISION HISTORY  (YYMMDD)
C   ??????  DATE WRITTEN
C   891214  Prologue converted to Version 4.0 format.  (BAB)
C***END PROLOGUE  DF1P
      DOUBLE PRECISION ALFA1,ALFA2,P1,P2,X,D1,D2
C***FIRST EXECUTABLE STATEMENT  DF1P
C  P1 = 1/7, P2 = 2/3
      DATA P1/0.1428571428571428D+00/
      DATA P2/0.6666666666666667D+00/
      ALFA1 = -0.25D0
      ALFA2 = -0.5D0
      D1=ABS(X-P1)
      D2=ABS(X-P2)
      DF1P = 0.0D+00
      IF(D1.NE.0.0D+00.AND.D2.NE.0.0D+00) DF1P = D1**ALFA1+D2**ALFA2
      RETURN
      END

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