program para_pt

      real x(100),y(100),xp(5),yp(5)
      
      xmin=0.0
      xmax=5.0
      ymin=0.0
      ymax=20.0
      i_ratio=0
      i_axis=0
      
      dx=(xmax-min)/99

      do i=1,100
        x(i)=xmin+(i-1)*dx
        y(i)=x(i)*x(i)
      enddo

      do i=1,5
        xp(i)=i
        yp(i)=xp(i)*xp(i)
      enddo

      n=100
      m=5
      isymbal=9

      i_dummy=pgopen('/xwin')

      call pgenv(xmin,xmax,ymin,ymax,i_ratio,i_axis)

      call pgline(100,x,y)

      call pgpt(m,xp,yp,isymbal)

      call pgclos

      end