'Parameters
fig : Figure
pos : tuple of 4 floats
position of the rectangle that will be divided
horizontal : list of :mod:`~mpl_toolkits.axes_grid.axes_size`
sizes for horizontal division
vertical : list of :mod:`~mpl_toolkits.axes_grid.axes_size`
sizes for vertical division
aspect : bool
if True, the overall rectangular area is reduced
so that the relative part of the horizontal and
vertical scales have the same scale.
anchor : {\'C\', \'SW\', \'S\', \'SE\', \'E\', \'NE\', \'N\', \'NW\', \'W\'}
placement of the reduced rectangle when *aspect* is True'

def __init__(self, fig, pos, horizontal, vertical, aspect=None, anchor=u'C'):

    self._fig = fig
    self._pos = pos
    self._horizontal = horizontal
    self._vertical = vertical
    self._anchor = anchor
    self._aspect = aspect
    self._xrefindex = 0
    self._yrefindex = 0
    self._locator = None
