(self)
return self.radius * cos(S.Pi/self._n)
The inradius of the RegularPolygon.

        The apothem/inradius is the radius of the inscribed circle.

        Returns
        =======

        apothem : number or instance of Basic

        See Also
        ========

        sympy.geometry.line.Segment.length, sympy.geometry.ellipse.Circle.radius

        Examples
        ========

        >>> from sympy import Symbol
        >>> from sympy.geometry import RegularPolygon, Point
        >>> radius = Symbol('r')
        >>> rp = RegularPolygon(Point(0, 0), radius, 4)
        >>> rp.apothem
        sqrt(2)*r/2
The inradius of the RegularPolygon.
The inradius of the RegularPolygon .
def apothem(self):
        """The inradius of the RegularPolygon.

        The apothem/inradius is the radius of the inscribed circle.

        Returns
        =======

        apothem : number or instance of Basic

        See Also
        ========

        sympy.geometry.line.Segment.length, sympy.geometry.ellipse.Circle.radius

        Examples
        ========

        >>> from sympy import Symbol
        >>> from sympy.geometry import RegularPolygon, Point
        >>> radius = Symbol('r')
        >>> rp = RegularPolygon(Point(0, 0), radius, 4)
        >>> rp.apothem
        sqrt(2)*r/2

        """
        return self.radius * cos(S.Pi/self._n)
def apothem ( self ) : return self . radius * cos ( S . Pi / self . _n )