Type()-checking for np.ndarray is overly restrictive to subclasses

[pkla]

Problem: In hausdorff.hausdorff_distance, the first assertion, that type(XA) is np.ndarray and type(XB) is np.ndarray, is overly restrictive as it disallows sub-classes of numpy.ndarray. For example, a common use-case is to call this function on the points of a PyVista mesh, which are stored in a pyvista.pyvista_ndarray. This object subclasses from numpy.ndarray and is functionally identical but this function raises an assertion error if an instance is passed in.

py-hausdorff/hausdorff/hausdorff.py

Lines 39 to 40 in cf13865

	def hausdorff_distance(XA, XB, distance='euclidean'):
	assert type(XA) is np.ndarray and type(XB) is np.ndarray, \

Steps to reproduce: Create a subclass of numpy.ndarray and pass an instance into hausdorff.hausdorff_distance.

import numpy as np
from hausdorff import hausdorff_distance

class my_ndarray(np.ndarray): pass
a = my_ndarray(np.array([5, 2]))
hausdorff_distance(a, a) # raises AssertionError

[pkla]

I made a pull request to fix this issue. See #16.

[mavillan]

Already merged it, thanks for contributing!