petls.sheaf_simplex_tree.apply_restriction_function

sheaf_simplex_tree.apply_restriction_function() → tuple[list[array], list[list[float]]]

Get coboundaries and filtrations

Returns:

tuple[list[np.array],list[list[float]]]

The first element of the tuple is a list of coboundary matrices, the second element is a list of filtrations (one list[float] per dimension)

Examples

>>> st = gudhi.simplex_tree(...)
>>> def my_restriction(simplex, coface, sst):
        ...
        return coeff # float
>>> extra_data = {}
>>> sst = sheaf_simplex_tree(st, extra_data, my_restriction)
>>> [coboundaries, filtrations] = sst.apply_restriction_function()
>>> print(coboundaries) 
    [   array([[-5., 0., 2.],
               [0., -5., 3.],
               [-3., 2., 0.]]), 
        array([[-3., 2., 5.]])
    ]
>>> print(filtrations)
[[0.0, 0.0, 0.0], [1.0, 1.0, 1.0], [1.0]]