SUBROUTINE GRUNG3
      DOUBLE PRECISION T1,T2,TD,ZO,EMA,PI,W,WC,X,Y
      DIMENSION X(50),Y(50)
      COMMON /GRUNGE/ I,TD,ZO,EMA,PI,W,WC
      COMMON /FIT/ X,Y
      T1=W*TD*1D-6
      T2=DSIN(T1)/DCOS(T1)
      X(I)=T2*W*W
      Y(I)=T2-2.*W/WC
      RETURN
      END