anchor.diff:      end subroutine plmap1
   
       subroutine plmap2(mapname,minx,maxx,miny,maxy)
  -      implicit none
         real(kind=plflt) minx, maxx, miny, maxy
         character*(*) mapname
   
  
positive.code:     interface
          subroutine plgxax( digmax, digits )
              use plplot_types
              integer(kind=plint) :: digmax, digits
          end subroutine plgxax
      end interface
  
negative.code:     interface
          subroutine plrgb1( r, g, b )
              use plplot_types
              implicit none
              integer(kind=plint) :: r, g, b
          end subroutine plrgb1
      end interface
  