Rips_complex/example_rips_complex_from_off_file.cpp
#include <gudhi/Rips_complex.h>
// to construct Rips_complex from a OFF file of points
#include <gudhi/Points_off_io.h>
#include <gudhi/Simplex_tree.h>
#include <iostream>
#include <string>
#include <vector>
void usage(int nbArgs, char * const progName) {
std::cerr << "Error: Number of arguments (" << nbArgs << ") is not correct\n";
std::cerr << "Usage: " << progName << " filename.off threshold dim_max [ouput_file.txt]\n";
std::cerr << " i.e.: " << progName << " ../../data/points/alphacomplexdoc.off 60.0\n";
exit(-1); // ----- >>
}
int main(int argc, char **argv) {
if ((argc != 4) && (argc != 5)) usage(argc, (argv[0] - 1));
std::string off_file_name(argv[1]);
double threshold = atof(argv[2]);
int dim_max = atoi(argv[3]);
// Type definitions
using Point = std::vector<float>;
using Simplex_tree = Gudhi::Simplex_tree<>;
using Filtration_value = Simplex_tree::Filtration_value;
// ----------------------------------------------------------------------------
// Init of a Rips complex from an OFF file
// ----------------------------------------------------------------------------
Gudhi::Points_off_reader<Point> off_reader(off_file_name);
Rips_complex rips_complex_from_file(off_reader.get_point_cloud(), threshold, Gudhi::Euclidean_distance());
std::streambuf* streambufffer;
std::ofstream ouput_file_stream;
if (argc == 5) {
ouput_file_stream.open(std::string(argv[4]));
streambufffer = ouput_file_stream.rdbuf();
} else {
streambufffer = std::cout.rdbuf();
}
Simplex_tree stree;
rips_complex_from_file.create_complex(stree, dim_max);
std::ostream output_stream(streambufffer);
// ----------------------------------------------------------------------------
// Display information about the Rips complex
// ----------------------------------------------------------------------------
output_stream << "Rips complex is of dimension " << stree.dimension() <<
" - " << stree.num_simplices() << " simplices - " <<
stree.num_vertices() << " vertices." << std::endl;
output_stream << "Iterator on Rips complex simplices in the filtration order, with [filtration value]:" <<
std::endl;
for (auto f_simplex : stree.filtration_simplex_range()) {
output_stream << " ( ";
for (auto vertex : stree.simplex_vertex_range(f_simplex)) {
output_stream << vertex << " ";
}
output_stream << ") -> " << "[" << stree.filtration(f_simplex) << "] ";
output_stream << std::endl;
}
ouput_file_stream.close();
return 0;
}
GUDHI  Version 2.0.0  - C++ library for Topological Data Analysis (TDA) and Higher Dimensional Geometry Understanding. Generated on Wed Apr 19 2017 22:26:16 for GUDHI by doxygen 1.8.11