Atan2(y,x)
    {
       global Pi

       return (x > 0 ? Atan(y/x)
              : ((y >= 0 AND x < 0) ? (Atan(y/x) + 3.14159)
                 : ((y < 0 AND x < 0) ? (Atan(y/x) - 3.14159)
                 : ((y > 0 AND x = 0) ? 3.14159/2
                 : ((y < 0 AND x = 0) ? -3.14159/2 : "")))))
    }


     SetFormat, Float, 0.3
        FileDelete, calc.txt
        Gui, Font, S12 Tahoma
        GUI, add, text , x10 Y10 h30 w100  , Current Pos x
        GUI, add, text , x160 Y10 h30 w100 , Current Pos z
        GUI, add, edit , x10 y30 W100  Vnumber1,
        GUI, add, edit , x160 y30 W100  Vnumber2,
        GUI, add, text , x10 Y70 h30 w100  , Destina Pos x
        GUI, add, text , x160 Y70 h30 w100 , Destina Pos z
        GUI, add, edit , x10 y100 W100  Vnumber3,
        GUI, add, edit , x160 y100 W100  Vnumber4,
        GUI, add, button,  x10 y150 h20 w40  gAdd , Time
        GUI, add, button,  x60 y150 h20 w80  gDiv , Heading
        GUI, add, button,  x10 y310 h20 w50  gClose, Close
        GUI, add, button,  x70 y310 h20 w50  gClear, Clear
        GUI, add, Edit, x10 y170 h100 w200 VOutcome ReadOnly,
        GUI, show, H350 W270, H1Z1 Calc
        return

        Add:
        sign = +
        gosub, calc
        Return

        Sub:
        sign = -
        gosub, calc
        Return

        Mult:
        sign = *
        gosub, calc
        Return

        Div:
        sign = /
        gosub, calc
        Return

        Close:
        ExitApp

         calc:
         GUI, submit, NoHide
         If sign = +
        {
        out := 0.002705*(sqrt((number3-number1)*(number3-number1)+(number4-number2)*(number4-number2)))
        }

         If sign = -
        {
                out := (number1 – number2)
        }
         If sign = *
        {
              out:= (number1 * number2)
         }
        If Sign = /
        {
            out := (atan2((number3-number1),(number4-number2)))
        }

        Fileappend,  %out% `r`n, calc.txt
        Fileread, list, calc.txt
        GuiControl, ,  Outcome, %list%
        Return

        Clear:
        FileDelete, calc.txt
        GUI, add, Edit, x10 y170 h100 w200 ReadOnly,
        return