*CMZ :          23/08/93  13.30.10  by  Jonathan Butterworth
*-- Author :
      SUBROUTINE FEQN (NCUT,F,FGAM,FNLIN)
      INTEGER NCUT
      DOUBLE PRECISION FGAM
      DOUBLE PRECISION F(NCUT), FNLIN(NCUT)
      INTEGER I, NCUTM1
      SAVE
      IF(NCUT.EQ.1) GOTO 20
      NCUTM1=NCUT-1
      DO 10 I=1,NCUTM1
      FNLIN(I)=F(I)-F(I+1)
 10   CONTINUE
 20   FNLIN(NCUT)=F(1)-FGAM
      RETURN
      END