anchor.diff:            write(STO,*)
         endif
         write(STO,*)
  -     1 '-fn          (default)  Treat subfaults as finite sources'
  +     1 '-fn                     Treat subfaults as finite sources ',
  +     2                                    '(default)'
         write(STO,*)
        1 '-pt                     Treat subfaults as point sources'
  +      write(STO,*)
  +     1 '-xy                     Treat all input coordinates as X-Y ',
  +     2                          'instead of lon-lat (in km)'
  +      if (str.eq.'long') then
  +          write(STO,*)
  +          write(STO,*)
  +     1 '    All input fault file and receiver location formats are the',
  +     2      ' same,'
  +          write(STO,*)
  +     1 '    except evlo, evla, stlo, and stla are treated ',
  +     2      'as kilometers from origin'
  +          write(STO,*)
  +     1 '    in Cartesian coordinates.'
  +          write(STO,*)
  +     1 '    Designed for problems where user is interested in cross-',
  +     2      'sections.'
  +          write(STO,*)
  +      endif
         if (str.eq.'long') then
             write(STO,*)
         endif
  
positive.code:       PARAMETER (NTHR=3)
        REAL*8 dl(NTHR),thr(NTHR)
        REAL*8 hylo,hyla,WMAX,EMAX,SMAX,NMAX,W,E,S,N,lo,la
        REAL*8 uE,uN,uZ,stdp,vp,vs,dens
        INTEGER nflt,FMAX
        PARAMETER (FMAX=1500)
        REAL*8 evlo(FMAX),evla(FMAX),evdp(FMAX),str(FMAX),dip(FMAX),
       1       rak(FMAX),dx(FMAX),dy(FMAX),slip(FMAX)
        INTEGER dir,flttyp
        dl(1) = 1.0d0 ! Amounts to move test location (deg)
        dl(2) = 0.1d0
        dl(3) = 0.05d0
        thr(1) = 0.5d0 ! Displacement thresholds (m)
        thr(2) = 0.01d0
        thr(3) = 0.001d0
        flttyp = 1
        call autohalfspace(vp,vs,dens)
        stdp = 0.0d0
        do 903 dir = 1,4
            lo = hylo
            la = hyla
  
negative.code: C----
        call gcmdln(ffmfile,fltfile,magfile,stafile,haffile,trgfile,
       1            dspfile,stnfile,stsfile,norfile,shrfile,coufile,
       2            gmtfile,flttyp,auto,incr,depth,xy)
        call dbggcmdln(ffmfile,fltfile,magfile,stafile,haffile,
       1                     trgfile,dspfile,stnfile,stsfile,norfile,
       2                     shrfile,coufile,gmtfile,flttyp,auto,incr)
  
  C----
  C Check for input fault source files, and whether output is specified
  