1 files changed, 68 insertions, 0 deletions
diff --git a/src/python/example/alpha_complex_diagram_persistence_from_off_file_example.py b/src/python/example/alpha_complex_diagram_persistence_from_off_file_example.py
new file mode 100755
index 00000000..b8f283b3
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+++ b/src/python/example/alpha_complex_diagram_persistence_from_off_file_example.py
@@ -0,0 +1,68 @@
+#!/usr/bin/env python
+
+import gudhi
+import argparse
+
+""" This file is part of the Gudhi Library - https://gudhi.inria.fr/ - which is released under MIT.
+    See file LICENSE or go to https://gudhi.inria.fr/licensing/ for full license details.
+    Author(s):       Vincent Rouvreau
+
+    Copyright (C) 2016 Inria
+
+    Modification(s):
+      - YYYY/MM Author: Description of the modification
+"""
+
+__author__ = "Vincent Rouvreau"
+__copyright__ = "Copyright (C) 2016 Inria"
+__license__ = "MIT"
+
+parser = argparse.ArgumentParser(
+    description="AlphaComplex creation from " "points read in a OFF file.",
+    epilog="Example: "
+    "example/alpha_complex_diagram_persistence_from_off_file_example.py "
+    "-f ../data/points/tore3D_300.off -a 0.6"
+    "- Constructs a alpha complex with the "
+    "points from the given OFF file.",
+)
+parser.add_argument("-f", "--file", type=str, required=True)
+parser.add_argument("-a", "--max_alpha_square", type=float, default=0.5)
+parser.add_argument("-b", "--band", type=float, default=0.0)
+parser.add_argument(
+    "--no-diagram",
+    default=False,
+    action="store_true",
+    help="Flag for not to display the diagrams",
+)
+
+args = parser.parse_args()
+
+with open(args.file, "r") as f:
+    first_line = f.readline()
+    if (first_line == "OFF\n") or (first_line == "nOFF\n"):
+        print("#####################################################################")
+        print("AlphaComplex creation from points read in a OFF file")
+
+        message = "AlphaComplex with max_edge_length=" + repr(args.max_alpha_square)
+        print(message)
+
+        alpha_complex = gudhi.AlphaComplex(off_file=args.file)
+        simplex_tree = alpha_complex.create_simplex_tree(
+            max_alpha_square=args.max_alpha_square
+        )
+
+        message = "Number of simplices=" + repr(simplex_tree.num_simplices())
+        print(message)
+
+        diag = simplex_tree.persistence()
+
+        print("betti_numbers()=")
+        print(simplex_tree.betti_numbers())
+
+        if args.no_diagram == False:
+            pplot = gudhi.plot_persistence_diagram(diag, band=args.band)
+            pplot.show()
+    else:
+        print(args.file, "is not a valid OFF file")
+
+    f.close()