anchor.diff:        IMPLICIT NONE
         REAL*8 pi,d2r
         PARAMETER (pi=4.0d0*atan(1.0d0),d2r=pi/180.0d0)
  -      REAL*8 uLOS,stlo,stla,uN,uE,uZ
  +      REAL*8 uLOS,stlo,stla,stdp,uN,uE,uZ
         REAL*8 az,incl,cosaz,cosinc,sinaz,sininc
         CHARACTER*40 ifile,ofile
         LOGICAL ex
  
positive.code: C----
  C Convert NEZ to LOS
  C----
     11 read (11,*,end=12) stlo,stla,uE,uN,uZ
            uLOS = uN*cosaz*cosinc
       1             + uE*sinaz*cosinc
       2                 - uZ*sininc
            write (12,*) stlo,stla,uLOS
            goto 11
     12 continue
  
        END
  
  
negative.code:       write(*,*)
       1 '-i INC    Look inclination (from horizontal)'
        write(*,*)
       1 '-f IFILE  Input vector displacement file (stlo stla stdp uE ',
       2                                                'uN uZ)'
        write(*,*)
       1 '-o OFILE  Output LOS displacement file (stlo stla stdp uLOS)'
        write (*,*)
       1 '-h        Online help (this message)'
        write (*,*)
  