anchor.diff:        write(*,*)
        1 '-clip CLIPFILE     Write outline of FFM to a file'
         write(*,*)
  +     1 '-clipseg CLIPFILE  Write outline of each segment in FFM to a ',
  +     2                    'file'
  +      write(*,*)
        1 '-trup TIME         Only include subfaults that rupture before ',
        2                    'TIME'
   C     1 '-t TIME        Only include patches that rupture before TIME ',
  
positive.code: C Read finite fault model
  C----
        call readffm(ifile,evlo,evla,evdp,str,dip,rak,dx,dy,slip,trup,
       1             hylo,hyla,nflt)
  
  C----
  C Write GMT-ready files
  
negative.code:               dx(ct+i) = dxr
                dy(ct+i) = dyr
                evdp(ct+i) = 1.0d3*evdp(ct+i)
                seg(ct+i) = g
    312     continue
            ct = ct + nx*ny
    313 continue
  