C     Plotting program for general purpose using postscript
      call init
      call readdata
      call viewport(0.2,0.2,0.8,0.8)
      call xyworld(0.0,0.0,1.0,1.0)
      call frame
      call plotd
      call fin
      stop
      end
      subroutine readdata
      common /maxmin/xmax,xmin,ymax,ymin,n
      common /dataxy/x1(100),y1(100)
      open (2,file='pg.data',status='OLD')
      do 10 i=1,100
        read(2,*,end=99) x1(i),y1(i)
   10 continue
   99 continue
      n=i-1
      xmax=x1(1)
      xmin=x1(1)
      ymax=y1(1)
      ymin=y1(1)
      do 20 i=2,n
       if(xmax.lt.x1(i)) xmax=x1(i)
       if(xmin.gt.x1(i)) xmin=x1(i)
       if(ymax.lt.y1(i)) ymax=y1(i)
       if(ymin.gt.y1(i)) ymin=y1(i)
   20 continue
      return
      end
      subroutine plotd
      common /maxmin/xmax,xmin,ymax,ymin,n
      common /dataxy/x1(100),y1(100)
      call linewidth(1.5)
      call linety(1)
      do 20 i=1,n
       x1(i)=(x1(i)-xmin)/(xmax-xmin)
       y1(i)=(y1(i)-ymin)/(ymax-ymin)
   20 continue
      call plot(x1(1),y1(1),3)
      do 30 i=2,n
        call plot(x1(i),y1(i),2)
   30 continue
      call stroke()
      call plot(0.9,-0.06,3)
      write(1,100) xmax
      call plot(0.4,-0.06,3)
      write(1,100) (xmax+xmin)/2.0
      call plot(-0.1,-0.06,3)
      write(1,100) xmin
      call plot(-0.2,0.98,3)
      write(1,100) ymax
      call plot(-0.2,0.48,3)
      write(1,100) (ymax+ymin)/2.0
      call plot(-0.2,-0.02,3)
      write(1,100) ymin
  100 format(1x,'(',1pe8.1,') show')
      continue
      return
      end
      subroutine frame
      common /maxmin/xmax,xmin,ymax,ymin,n
      common /dataxy/x1(100),y1(100)
      call linewidth(1.0)
      call rect(0.0,0.0,1.0,1.0,0.0,1.0,1)
      call textx(0.75,0.0,1,'x')
      nx=2
      do 10 ix=1,nx-1
       x=float(ix)/float(nx)
       dy=0.03
       call plot(x,0.0,3)
       call plot(x,dy,2)
       call stroke()
   10 continue
      call texty(0.0,0.75,1,'y')
      ny=2
      do 20 iy=1,ny-1
       y=float(iy)/float(ny)
       dx=0.03
       call plot(0.0,y,3)
       call plot(dx,y,2)
       call stroke()
   20 continue
      return
      end