def function v
    Error.call "Line::function : unable to execute function : the vector v_dir is null" if self.nil?
    Error.call "Line::functionx : invalid lambda ( #{v} ) value" if !v.is_a?Numeric

    lp = parametric()
    Point.new(lp[:x][:p] + v * lp[:x][:v], lp[:y][:p] + v * lp[:y][:v], lp[:z][:p] + v * lp[:z][:v])
  end
def function v
    Error.call "Line::function : unable to execute function : the vector v_dir is null" if self.nil?
    Error.call "Line::functionx : invalid lambda ( #{v} ) value" if !v.is_a?Numeric

    lp = parametric()
    Point.new(lp[:x][:p] + v * lp[:x][:v], lp[:y][:p] + v * lp[:y][:v], lp[:z][:p] + v * lp[:z][:v])
  end
This function returns the point on the line where x = v * vx + px, ...
 == Parameters:
 v::
     The value defined the point wich will be return.
 == Returns:
 The choosed Point one the line from v (lambda)