1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
/* 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): Siargey Kachanovich
*
* Copyright (C) 2015 INRIA Sophia Antipolis-Méditerranée (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 <iostream>
#include <fstream>
#include <ctime>
#include <sys/types.h>
#include <sys/stat.h>
#include "gudhi/Simplex_tree.h"
#include "gudhi/Witness_complex.h"
#include "gudhi/Landmark_choice_by_random_point.h"
#include "gudhi/reader_utils.h"
using namespace Gudhi;
using namespace Gudhi::witness_complex;
typedef std::vector< Vertex_handle > typeVectorVertex;
typedef std::vector< std::vector <double> > Point_Vector;
typedef Witness_complex< Simplex_tree<> > WitnessComplex;
/**
* \brief Customized version of read_points
* which takes into account a possible nbP first line
*
*/
inline void
read_points_cust ( std::string file_name , std::vector< std::vector< double > > & points)
{
std::ifstream in_file (file_name.c_str(),std::ios::in);
if(!in_file.is_open())
{
std::cerr << "Unable to open file " << file_name << std::endl;
return;
}
std::string line;
double x;
while( getline ( in_file , line ) )
{
std::vector< double > point;
std::istringstream iss( line );
while(iss >> x) { point.push_back(x); }
if (point.size() != 1)
points.push_back(point);
}
in_file.close();
}
/** Write a gnuplot readable file.
* Data range is a random access range of pairs (arg, value)
*/
template < typename Data_range >
void write_data( Data_range & data, std::string filename )
{
std::ofstream ofs(filename, std::ofstream::out);
for (auto entry: data)
ofs << entry.first << ", " << entry.second << "\n";
ofs.close();
}
int main (int argc, char * const argv[])
{
if (argc != 3)
{
std::cerr << "Usage: " << argv[0]
<< " path_to_point_file nbL \n";
return 0;
}
std::string file_name = argv[1];
int nbL = atoi(argv[2]);
clock_t start, end;
// Construct the Simplex Tree
Simplex_tree<> simplex_tree;
// Read the point file
Point_Vector point_vector;
read_points_cust(file_name, point_vector);
std::cout << "Successfully read " << point_vector.size() << " points.\n";
std::cout << "Ambient dimension is " << point_vector[0].size() << ".\n";
// Choose landmarks
start = clock();
std::vector<std::vector< int > > knn;
Landmark_choice_by_random_point(point_vector, nbL, knn);
end = clock();
std::cout << "Landmark choice for " << nbL << " landmarks took "
<< (double)(end-start)/CLOCKS_PER_SEC << " s. \n";
// Compute witness complex
start = clock();
WitnessComplex(knn, simplex_tree, nbL, point_vector[0].size());
end = clock();
std::cout << "Witness complex took "
<< (double)(end-start)/CLOCKS_PER_SEC << " s. \n";
}
|