anchor.diff:        cos_omega = cos(omega)
         y_shear = -0.5*yrange*sin_omega
         z_shear = 0.5*zrange*cos_omega
  -      call plptex3( &
  -         xmax, ymid, zmax -(zmax-0.2)*((i-1)/dble(NSHEAR-1)), &
  +      z_location = zmax -(zmax-0.2)*((i-1)/dble(NSHEAR-1))
  +      call plptex3( &
  +         xmax, ymid, z_location, &
            x_inclination, y_inclination, z_inclination, &
            x_shear, y_shear, z_shear, &
            0.5_plflt, "shear for x = x#dmax#u")
  
positive.code:       cos_omega = cos(omega)
        y_shear = 0.5*yrange*cos_omega
        x_shear = 0.5*xrange*sin_omega
        call plptex3( &
           xmid, ymax -(ymax-0.2)*(dble(i-1)/dble(NSHEAR-1)), zmin, &
           x_inclination, y_inclination, z_inclination, &
           x_shear, y_shear, z_shear, &
           0.5_plflt, "shear for z = z#dmin#u")
  
negative.code:         xmid = 0.5*(xmax + xmin), xrange = xmax - xmin,                    &
          ymin=0., ymax=1.0, ymid = 0.5*(ymax + ymin), yrange = ymax - ymin, &
          zmin=0., zmax=1.0, zmid = 0.5*(zmax + zmin), zrange = zmax - zmin
          real(PLFLT) :: y_location, z_location, &
          x_inclination, y_inclination, z_inclination,       &
          x_shear, y_shear, z_shear,                         &
          omega, sin_omega, cos_omega, domega
     integer     :: i, j
     real(PLFLT) :: radius, pitch, xpos, ypos, zpos
  