use "math"

struct -vector2d
    init &xpos -double
    init &ypos -double

    fun -void !init -double &x -double &y
        set &xpos $x
        set &ypos $y
        return true
    endfun

    fun -string !toString
        tostring $xpos &x1
        tostring $ypos &y1
        add "(" $x1 &store
        add $store ", " &store
        add $store $y1 &store
        add $store ")" &store
        return $store
    endfun

    fun -double !atan2
        pusharg $ypos $xpos
        !math:atan2 &store
        return $store
    endfun

    fun -double !modulus
        multiply $xpos $xpos &x2
        multiply $ypos $ypos &y2
        add $x2 $y2 &z2
        pusharg $z2
        !math:sqrt &z
        return $z
    endfun
endstruct

struct -line2d
    init &gradient -double
    init &yint -double

    fun -void !initGI -double &g -double &y
        set &gradient $g
        set &yint $y
        return true
    endfun

    fun -void !initTP -point &p1 -point &p2
        subtract $p2.ypos $p1.ypos &rise
        subtract $p2.xpos $p1.xpos &run
        divide $rise $run &gradient
        
        multiply $gradient $p1.xpos &store
        subtract $p1.ypos $store &yint
        return true
    endfun

    fun -vector2d !getPoint -double &x
        multiply $gradient $x &store
        add $store $yint &y
        init &ans -vector2d
        pusharg $x $y
        !ans.init &store
        return $ans
    endfun
endstruct

init &line -line2d
pusharg 3 1
!line.initGI &store

pusharg 3
!line.getPoint &store

stdlnout $store.xpos
stdlnout $store.ypos