Add witness_complex_from_nearest_landmark_table.py

git-svn-id: svn+ssh://scm.gforge.inria.fr/svnroot/gudhi/branches/ST_cythonize@2182 636b058d-ea47-450e-bf9e-a15bfbe3eedb

Former-commit-id: 5e9efcf4c6e50f0864cf473d649dfa26b4ef2cf4

2 files changed, 47 insertions, 1 deletions

diff --git a/src/cython/cython/witness_complex.pyx b/src/cython/cython/witness_complex.pyx
index e0d8b1e3..21624fe3 100644
--- a/src/cython/cython/witness_complex.pyx
+++ b/src/cython/cython/witness_complex.pyx
@@ -44,7 +44,7 @@ cdef class WitnessComplex:
     cdef Witness_complex_interface * thisptr
 
     # Fake constructor that does nothing but documenting the constructor
-    def __init__(self, points=None, number_of_landmarks=5):
+    def __init__(self, nearest_landmark_table=None):
         """WitnessComplex constructor.
 
         :param nearest_landmark_table: A list of nearest landmark.
diff --git a/src/cython/example/witness_complex_from_nearest_landmark_table.py b/src/cython/example/witness_complex_from_nearest_landmark_table.py
new file mode 100755
index 00000000..00b946b1
--- /dev/null
+++ b/src/cython/example/witness_complex_from_nearest_landmark_table.py
@@ -0,0 +1,46 @@
+#!/usr/bin/env python
+
+from gudhi import WitnessComplex, SimplexTree
+
+"""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 <http://www.gnu.org/licenses/>.
+"""
+
+__author__ = "Vincent Rouvreau"
+__copyright__ = "Copyright (C) 2016 INRIA"
+__license__ = "GPL v3"
+
+print("#####################################################################")
+print("WitnessComplex creation from nearest landmark table")
+nearest_landmark_table = [[[0, 0], [1, 1], [2, 2], [3, 3], [4, 4]],
+                          [[1, 0], [2, 1], [3, 2], [4, 3], [0, 4]],
+                          [[2, 0], [3, 1], [4, 2], [0, 3], [1, 4]],
+                          [[3, 0], [4, 1], [0, 2], [1, 3], [2, 4]],
+                          [[4, 0], [0, 1], [1, 2], [2, 3], [3, 4]]]
+
+witness_complex = WitnessComplex(nearest_landmark_table=nearest_landmark_table)
+simplex_tree = witness_complex.create_simplex_tree(max_alpha_square=4.1)
+
+message = "Number of simplices: " + repr(simplex_tree.num_simplices())
+print(message)
+
+diag = simplex_tree.persistence(min_persistence=-0.1, homology_coeff_field=11)
+print(diag)