anchor.diff:        xsec = 0
         xz = 0
         clip = 'none'
  +      datain = 0
         do 100 i = 1,5
             ref(i) = -1.0d0
     100 continue
  
positive.code:       REAL*8 pi,d2r
        PARAMETER (pi=4.0d0*datan(1.0d0),d2r=pi/180.0d0)
        CHARACTER*40 ofile
        CHARACTER*200 clip
        REAL*8 x1,x2,y1,y2,dx,dy,dz,dd,ref(5),dist,az,lo,la
        REAL*8 x,y,z,xx(1000),yy(1000),zsave,tmp
        INTEGER i,j,nx,ny,p,xsec,xz,nn,io
  
  C----
  C Get parameters from the command line
  
negative.code: C----------------------------------------------------------------------C
  
        SUBROUTINE gcmdln(x1,x2,nx,dx,y1,y2,ny,dy,z,ofile,p,ref,xsec,xz,
       1                  clip,datain)
        IMPLICIT none
        CHARACTER*40 tag,ofile
        CHARACTER*200 clip
        REAL*8 x1,x2,y1,y2,z,dx,dy,ref(5)
        INTEGER narg,i,j,nx,ny,p,xsec,xz,datain
  C Initialize variable values
        x1 = 0.0d0
        x2 = 0.0d0
  