summaryrefslogtreecommitdiff
path: root/src/Persistence_representations/include/gudhi/Persistence_landscape_on_grid_exact.h
diff options
context:
space:
mode:
Diffstat (limited to 'src/Persistence_representations/include/gudhi/Persistence_landscape_on_grid_exact.h')
-rw-r--r--src/Persistence_representations/include/gudhi/Persistence_landscape_on_grid_exact.h108
1 files changed, 0 insertions, 108 deletions
diff --git a/src/Persistence_representations/include/gudhi/Persistence_landscape_on_grid_exact.h b/src/Persistence_representations/include/gudhi/Persistence_landscape_on_grid_exact.h
deleted file mode 100644
index 52f24195..00000000
--- a/src/Persistence_representations/include/gudhi/Persistence_landscape_on_grid_exact.h
+++ /dev/null
@@ -1,108 +0,0 @@
-/* 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): Mathieu Carriere
- *
- * Copyright (C) 2018 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/>.
- */
-
-#ifndef LANDSCAPE_H_
-#define LANDSCAPE_H_
-
-// gudhi include
-#include <gudhi/read_persistence_from_file.h>
-#include <gudhi/common_persistence_representations.h>
-#include <gudhi/Debug_utils.h>
-
-// standard include
-#include <cmath>
-#include <iostream>
-#include <vector>
-#include <limits>
-#include <fstream>
-#include <sstream>
-#include <algorithm>
-#include <string>
-#include <utility>
-#include <functional>
-
-namespace Gudhi {
-namespace Persistence_representations {
-
-/**
- * \class Persistence_landscape_on_grid_exact gudhi/Persistence_landscape_on_grid_exact.h
- * \brief A class implementing exact persistence landscapes by approximating them on a collection of grid points
- *
- * \ingroup Persistence_representations
- *
- * \details
- * In this class, we propose a way to approximate landscapes by sampling the x-axis of the persistence diagram and evaluating the (exact) landscape functions on the sample projections onto the diagonal. Note that this is a different approximation scheme
- * from the one proposed in Persistence_landscape_on_grid, which puts a grid on the diagonal, maps the persistence intervals on this grid and computes the (approximate) landscape functions on the samples.
- * Hence, the difference is that we do not modify the diagram in this implementation, but the code can be slower to run.
-**/
-
-class Persistence_landscape_on_grid_exact {
-
- protected:
- Persistence_diagram diagram;
- int res_x, nb_ls;
- double min_x, max_x;
-
- public:
-
- /** \brief Persistence_landscape_on_grid_exact constructor.
- * \ingroup Persistence_landscape_on_grid_exact
- *
- * @param[in] _diagram persistence diagram.
- * @param[in] _nb_ls number of landscape functions.
- * @param[in] _min_x minimum value of samples.
- * @param[in] _max_x maximum value of samples.
- * @param[in] _res_x number of samples.
- *
- */
- Persistence_landscape_on_grid_exact(const Persistence_diagram & _diagram, int _nb_ls = 5, double _min_x = 0.0, double _max_x = 1.0, int _res_x = 10){diagram = _diagram; nb_ls = _nb_ls; min_x = _min_x; max_x = _max_x; res_x = _res_x;}
-
- /** \brief Computes the landscape approximation of a diagram.
- * \ingroup Persistence_landscape_on_grid_exact
- *
- */
- std::vector<std::vector<double> > vectorize() const {
- std::vector<std::vector<double> > ls; for(int i = 0; i < nb_ls; i++) ls.emplace_back();
- int num_pts = diagram.size(); double step = (max_x - min_x)/(res_x - 1);
-
- std::vector<std::vector<double> > ls_t; for(int i = 0; i < res_x; i++) ls_t.emplace_back();
- for(int j = 0; j < num_pts; j++){
- double px = diagram[j].first; double py = diagram[j].second; double mid = (px+py)/2;
- int first = std::ceil((px-min_x)/step); int middle = std::ceil((mid-min_x)/step); int last = std::ceil((py-min_x)/step); double x = min_x + first*step;
- for(int i = first; i < middle; i++){ double value = std::sqrt(2)*(x-px); ls_t[i].push_back(value); x += step; }
- for(int i = middle; i < last; i++){ double value = std::sqrt(2)*(py-x); ls_t[i].push_back(value); x += step; }
- }
-
- for(int i = 0; i < res_x; i++){
- std::sort(ls_t[i].begin(), ls_t[i].end(), [](const double & a, const double & b){return a > b;});
- int nb_events_i = ls_t[i].size();
- for (int j = 0; j < nb_ls; j++){ if(j < nb_events_i) ls[j].push_back(ls_t[i][j]); else ls[j].push_back(0); }
- }
-
- return ls;
- }
-
-}; // class Persistence_landscape_on_grid_exact
-} // namespace Persistence_representations
-} // namespace Gudhi
-
-#endif // LANDSCAPE_H_