From 8d7329f3e5ad843e553c3c5503cecc28ef2eead6 Mon Sep 17 00:00:00 2001 From: Gard Spreemann Date: Thu, 20 Apr 2017 11:10:45 +0200 Subject: GUDHI 2.0.0 as released by upstream in a tarball. --- cython/cython/subsampling.pyx | 140 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 140 insertions(+) create mode 100644 cython/cython/subsampling.pyx (limited to 'cython/cython/subsampling.pyx') diff --git a/cython/cython/subsampling.pyx b/cython/cython/subsampling.pyx new file mode 100644 index 00000000..894a4fbe --- /dev/null +++ b/cython/cython/subsampling.pyx @@ -0,0 +1,140 @@ +from cython cimport numeric +from libcpp.vector cimport vector +from libcpp.string cimport string +from libcpp cimport bool +import os + +"""This file is part of the Gudhi Library. The Gudhi library + (Geometric Understanding in Higher Dimensions) is a generic C++ + library for computational topology. + + Author(s): Vincent Rouvreau + + Copyright (C) 2016 INRIA + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +""" + +__author__ = "Vincent Rouvreau" +__copyright__ = "Copyright (C) 2016 INRIA" +__license__ = "GPL v3" + +cdef extern from "Subsampling_interface.h" namespace "Gudhi::subsampling": + vector[vector[double]] subsampling_n_farthest_points(vector[vector[double]] points, unsigned nb_points) + vector[vector[double]] subsampling_n_farthest_points(vector[vector[double]] points, unsigned nb_points, unsigned starting_point) + vector[vector[double]] subsampling_n_farthest_points_from_file(string off_file, unsigned nb_points) + vector[vector[double]] subsampling_n_farthest_points_from_file(string off_file, unsigned nb_points, unsigned starting_point) + vector[vector[double]] subsampling_n_random_points(vector[vector[double]] points, unsigned nb_points) + vector[vector[double]] subsampling_n_random_points_from_file(string off_file, unsigned nb_points) + vector[vector[double]] subsampling_sparsify_points(vector[vector[double]] points, double min_squared_dist) + vector[vector[double]] subsampling_sparsify_points_from_file(string off_file, double min_squared_dist) + +def choose_n_farthest_points(points=None, off_file='', nb_points=0, starting_point = ''): + """Subsample by a greedy strategy of iteratively adding the farthest point + from the current chosen point set to the subsampling. + The iteration starts with the landmark `starting point`. + + :param points: The input point set. + :type points: vector[vector[double]]. + + Or + + :param off_file: An OFF file style name. + :type off_file: string + + :param nb_points: Number of points of the subsample. + :type nb_points: unsigned. + :param starting_point: The iteration starts with the landmark `starting \ + point`,which is the index of the poit to start with. If not set, this \ + index is choosen randomly. + :type starting_point: unsigned. + :returns: The subsample point set. + :rtype: vector[vector[double]] + """ + if off_file is not '': + if os.path.isfile(off_file): + if starting_point is '': + return subsampling_n_farthest_points_from_file(str.encode(off_file), + nb_points) + else: + return subsampling_n_farthest_points_from_file(str.encode(off_file), + nb_points, + starting_point) + else: + print("file " + off_file + " not found.") + else: + if points is None: + # Empty points + points=[] + if starting_point is '': + return subsampling_n_farthest_points(points, nb_points) + else: + return subsampling_n_farthest_points(points, nb_points, + starting_point) + +def pick_n_random_points(points=None, off_file='', nb_points=0): + """Subsample a point set by picking random vertices. + + :param points: The input point set. + :type points: vector[vector[double]]. + + Or + + :param off_file: An OFF file style name. + :type off_file: string + + :param nb_points: Number of points of the subsample. + :type nb_points: unsigned. + :returns: The subsample point set. + :rtype: vector[vector[double]] + """ + if off_file is not '': + if os.path.isfile(off_file): + return subsampling_n_random_points_from_file(str.encode(off_file), + nb_points) + else: + print("file " + off_file + " not found.") + else: + if points is None: + # Empty points + points=[] + return subsampling_n_random_points(points, nb_points) + +def sparsify_point_set(points=None, off_file='', min_squared_dist=0.0): + """Subsample a point set by picking random vertices. + + :param points: The input point set. + :type points: vector[vector[double]]. + + Or + + :param off_file: An OFF file style name. + :type off_file: string + + :param min_squared_dist: Number of points of the subsample. + :type min_squared_dist: unsigned. + :returns: The subsample point set. + :rtype: vector[vector[double]] + """ + if off_file is not '': + if os.path.isfile(off_file): + return subsampling_sparsify_points_from_file(str.encode(off_file), + min_squared_dist) + else: + print("file " + off_file + " not found.") + else: + if points is None: + # Empty points + points=[] + return subsampling_sparsify_points(points, min_squared_dist) -- cgit v1.2.3