diff options
Diffstat (limited to 'example/Persistence_representations/persistence_landscape_on_grid.cpp')
-rw-r--r-- | example/Persistence_representations/persistence_landscape_on_grid.cpp | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/example/Persistence_representations/persistence_landscape_on_grid.cpp b/example/Persistence_representations/persistence_landscape_on_grid.cpp new file mode 100644 index 00000000..b201b397 --- /dev/null +++ b/example/Persistence_representations/persistence_landscape_on_grid.cpp @@ -0,0 +1,82 @@ +/* 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): Pawel Dlotko + * + * Copyright (C) 2016 INRIA (France) + * + * 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/>. + */ + +#include <gudhi/Persistence_landscape_on_grid.h> + +#include <iostream> +#include <utility> +#include <vector> + +using Persistence_landscape_on_grid = Gudhi::Persistence_representations::Persistence_landscape_on_grid; + +int main(int argc, char** argv) { + // create two simple vectors with birth--death pairs: + + std::vector<std::pair<double, double> > persistence1; + std::vector<std::pair<double, double> > persistence2; + + persistence1.push_back(std::make_pair(1, 2)); + persistence1.push_back(std::make_pair(6, 8)); + persistence1.push_back(std::make_pair(0, 4)); + persistence1.push_back(std::make_pair(3, 8)); + + persistence2.push_back(std::make_pair(2, 9)); + persistence2.push_back(std::make_pair(1, 6)); + persistence2.push_back(std::make_pair(3, 5)); + persistence2.push_back(std::make_pair(6, 10)); + + // create two persistence landscapes based on persistence1 and persistence2: + Persistence_landscape_on_grid l1(persistence1, 0, 11, 20); + Persistence_landscape_on_grid l2(persistence2, 0, 11, 20); + + // This is how to compute integral of landscapes: + std::cout << "Integral of the first landscape : " << l1.compute_integral_of_landscape() << std::endl; + std::cout << "Integral of the second landscape : " << l2.compute_integral_of_landscape() << std::endl; + + // And here how to write landscapes to stream: + std::cout << "l1 : " << l1 << std::endl; + std::cout << "l2 : " << l2 << std::endl; + + // here are the maxima of the functions: + std::cout << "Maximum of l1 : " << l1.compute_maximum() << std::endl; + std::cout << "Maximum of l2 : " << l2.compute_maximum() << std::endl; + + // here are the norms of landscapes: + std::cout << "L^1 Norm of l1 : " << l1.compute_norm_of_landscape(1.) << std::endl; + std::cout << "L^1 Norm of l2 : " << l2.compute_norm_of_landscape(1.) << std::endl; + + // here is the average of landscapes: + Persistence_landscape_on_grid average; + average.compute_average({&l1, &l2}); + std::cout << "average : " << average << std::endl; + + // here is the distance of landscapes: + std::cout << "Distance : " << l1.distance(l2) << std::endl; + + // here is the scalar product of landscapes: + std::cout << "Scalar product : " << l1.compute_scalar_product(l2) << std::endl; + + // here is how to create a file which is suitable for visualization via gnuplot: + average.plot("average_landscape"); + + return 0; +} |