PROGRAM INTS
      character*80 FN
c     integral from spectral part
      if(iargc().ne.3)then
       WRITE(*,*)' usage: ints fn wmin wmax'
       stop
      endif
      call getarg(2,FN)
      read(FN,*)wmin
      call getarg(3,FN)
      read(FN,*)wmax
      call getarg(1,FN)
      open(44,file=FN)
      ai=0.0
      np=0
      xm=0.
1     read(44,*,end=99,err=99)x,y
      np=np+1
      if(np.gt.1.and.x.ge.wmin.and.x.le.wmax)ai=ai+abs(x-xm)*y
      xm=x
      goto 1
99    close(44)
      write(6,600)np,ai
600   format(i5,g20.6)
      end