program define points2
        version 4.0

        local x = "`1'"
        local y = "`2'"
        local sz1=`3'
        local sm1=`4'

        tempvar xp yp sm sz

        gen `xp' = $AX * `x' + $BX
        gen `yp' = $AY * `y' + $BY
        gen `sz' = `sz1'
        gen `sm' = `sm1'

        gph vpoint `yp' `xp' `sz' `sm'

end