diff options
Diffstat (limited to 'src/python/gudhi/simplex_tree.pyx')
| -rw-r--r-- | src/python/gudhi/simplex_tree.pyx | 102 |
1 files changed, 85 insertions, 17 deletions
diff --git a/src/python/gudhi/simplex_tree.pyx b/src/python/gudhi/simplex_tree.pyx index be08a3a1..a4914184 100644 --- a/src/python/gudhi/simplex_tree.pyx +++ b/src/python/gudhi/simplex_tree.pyx @@ -9,14 +9,16 @@ from cython.operator import dereference, preincrement from libc.stdint cimport intptr_t -import numpy -from numpy import array as np_array +import numpy as np cimport gudhi.simplex_tree __author__ = "Vincent Rouvreau" __copyright__ = "Copyright (C) 2016 Inria" __license__ = "MIT" +cdef bool callback(vector[int] simplex, void *blocker_func): + return (<object>blocker_func)(simplex) + # SimplexTree python interface cdef class SimplexTree: """The simplex tree is an efficient and flexible data structure for @@ -39,13 +41,29 @@ cdef class SimplexTree: cdef Simplex_tree_persistence_interface * pcohptr # Fake constructor that does nothing but documenting the constructor - def __init__(self): + def __init__(self, other = None): """SimplexTree constructor. + + :param other: If `other` is `None` (default value), an empty `SimplexTree` is created. + If `other` is a `SimplexTree`, the `SimplexTree` is constructed from a deep copy of `other`. + :type other: SimplexTree (Optional) + :returns: An empty or a copy simplex tree. + :rtype: SimplexTree + + :raises TypeError: In case `other` is neither `None`, nor a `SimplexTree`. + :note: If the `SimplexTree` is a copy, the persistence information is not copied. If you need it in the clone, + you have to call :func:`compute_persistence` on it even if you had already computed it in the original. """ # The real cython constructor - def __cinit__(self): - self.thisptr = <intptr_t>(new Simplex_tree_interface_full_featured()) + def __cinit__(self, other = None): + if other: + if isinstance(other, SimplexTree): + self.thisptr = _get_copy_intptr(other) + else: + raise TypeError("`other` argument requires to be of type `SimplexTree`, or `None`.") + else: + self.thisptr = <intptr_t>(new Simplex_tree_interface_full_featured()) def __dealloc__(self): cdef Simplex_tree_interface_full_featured* ptr = self.get_ptr() @@ -64,6 +82,21 @@ cdef class SimplexTree: """ return self.pcohptr != NULL + def copy(self): + """ + :returns: A simplex tree that is a deep copy of itself. + :rtype: SimplexTree + + :note: The persistence information is not copied. If you need it in the clone, you have to call + :func:`compute_persistence` on it even if you had already computed it in the original. + """ + stree = SimplexTree() + stree.thisptr = _get_copy_intptr(self) + return stree + + def __deepcopy__(self): + return self.copy() + def filtration(self, simplex): """This function returns the filtration value for a given N-simplex in this simplicial complex, or +infinity if it is not in the complex. @@ -412,7 +445,7 @@ cdef class SimplexTree: """This function retrieves good values for extended persistence, and separate the diagrams into the Ordinary, Relative, Extended+ and Extended- subdiagrams. - :param homology_coeff_field: The homology coefficient field. Must be a prime number. Default value is 11. + :param homology_coeff_field: The homology coefficient field. Must be a prime number. Default value is 11. Max is 46337. :type homology_coeff_field: int :param min_persistence: The minimum persistence value (i.e., the absolute value of the difference between the persistence diagram point coordinates) to take into account (strictly greater than min_persistence). @@ -444,12 +477,33 @@ cdef class SimplexTree: persistence_result = self.pcohptr.get_persistence() return self.get_ptr().compute_extended_persistence_subdiagrams(persistence_result, min_persistence) + def expansion_with_blocker(self, max_dim, blocker_func): + """Expands the Simplex_tree containing only a graph. Simplices corresponding to cliques in the graph are added + incrementally, faces before cofaces, unless the simplex has dimension larger than `max_dim` or `blocker_func` + returns `True` for this simplex. + + The function identifies a candidate simplex whose faces are all already in the complex, inserts it with a + filtration value corresponding to the maximum of the filtration values of the faces, then calls `blocker_func` + with this new simplex (represented as a list of int). If `blocker_func` returns `True`, the simplex is removed, + otherwise it is kept. The algorithm then proceeds with the next candidate. + + .. warning:: + Several candidates of the same dimension may be inserted simultaneously before calling `block_simplex`, so + if you examine the complex in `block_simplex`, you may hit a few simplices of the same dimension that have + not been vetted by `block_simplex` yet, or have already been rejected but not yet removed. + + :param max_dim: Expansion maximal dimension value. + :type max_dim: int + :param blocker_func: Blocker oracle. + :type blocker_func: Callable[[List[int]], bool] + """ + self.get_ptr().expansion_with_blockers_callback(max_dim, callback, <void*>blocker_func) def persistence(self, homology_coeff_field=11, min_persistence=0, persistence_dim_max = False): """This function computes and returns the persistence of the simplicial complex. :param homology_coeff_field: The homology coefficient field. Must be a - prime number. Default value is 11. + prime number. Default value is 11. Max is 46337. :type homology_coeff_field: int :param min_persistence: The minimum persistence value to take into account (strictly greater than min_persistence). Default value is @@ -472,7 +526,7 @@ cdef class SimplexTree: when you do not want the list :func:`persistence` returns. :param homology_coeff_field: The homology coefficient field. Must be a - prime number. Default value is 11. + prime number. Default value is 11. Max is 46337. :type homology_coeff_field: int :param min_persistence: The minimum persistence value to take into account (strictly greater than min_persistence). Default value is @@ -542,7 +596,11 @@ cdef class SimplexTree: function to be launched first. """ assert self.pcohptr != NULL, "compute_persistence() must be called before persistence_intervals_in_dimension()" - return np_array(self.pcohptr.intervals_in_dimension(dimension)) + piid = np.array(self.pcohptr.intervals_in_dimension(dimension)) + # Workaround https://github.com/GUDHI/gudhi-devel/issues/507 + if len(piid) == 0: + return np.empty(shape = [0, 2]) + return piid def persistence_pairs(self): """This function returns a list of persistence birth and death simplices pairs. @@ -583,8 +641,8 @@ cdef class SimplexTree: """ assert self.pcohptr != NULL, "lower_star_persistence_generators() requires that persistence() be called first." gen = self.pcohptr.lower_star_generators() - normal = [np_array(d).reshape(-1,2) for d in gen.first] - infinite = [np_array(d) for d in gen.second] + normal = [np.array(d).reshape(-1,2) for d in gen.first] + infinite = [np.array(d) for d in gen.second] return (normal, infinite) def flag_persistence_generators(self): @@ -602,19 +660,19 @@ cdef class SimplexTree: assert self.pcohptr != NULL, "flag_persistence_generators() requires that persistence() be called first." gen = self.pcohptr.flag_generators() if len(gen.first) == 0: - normal0 = numpy.empty((0,3)) + normal0 = np.empty((0,3)) normals = [] else: l = iter(gen.first) - normal0 = np_array(next(l)).reshape(-1,3) - normals = [np_array(d).reshape(-1,4) for d in l] + normal0 = np.array(next(l)).reshape(-1,3) + normals = [np.array(d).reshape(-1,4) for d in l] if len(gen.second) == 0: - infinite0 = numpy.empty(0) + infinite0 = np.empty(0) infinites = [] else: l = iter(gen.second) - infinite0 = np_array(next(l)) - infinites = [np_array(d).reshape(-1,2) for d in l] + infinite0 = np.array(next(l)) + infinites = [np.array(d).reshape(-1,2) for d in l] return (normal0, normals, infinite0, infinites) def collapse_edges(self, nb_iterations = 1): @@ -639,3 +697,13 @@ cdef class SimplexTree: self.thisptr = <intptr_t>(ptr.collapse_edges(nb_iter)) # Delete old pointer del ptr + + def __eq__(self, other:SimplexTree): + """Test for structural equality + :returns: True if the 2 simplex trees are equal, False otherwise. + :rtype: bool + """ + return dereference(self.get_ptr()) == dereference(other.get_ptr()) + +cdef intptr_t _get_copy_intptr(SimplexTree stree) nogil: + return <intptr_t>(new Simplex_tree_interface_full_featured(dereference(stree.get_ptr()))) |