write_csv_file.cpp

#include <iostream>
#include <string>
#include <vector>
#include <fstream>
#include <cstdlib>


struct perfStats {
  std::string detectorType;
  std::string descriptorType;
  std::string matchingType;
  std::string selectorType;
  int   numKeyPointsPerframe[10];
  int   numKeyPointsPerROI[10];
  int   numMatchedKeyPoints[10];
  double detectorTime[10];
  double descriptorTime[10];
  double MatcherTime[10];
};


// please see https://en.cppreference.com/w/cpp/io/basic_istream
int main(int argc, char *argv[]) {

  // init det/des combinations container, then fill it 
  std::vector<perfStats> combinations;
  /// TODO: fill combinations...
  
  std::string filename = "../data.csv";
  std::ofstream output_stream(filename, std::ios::binary);

  if (!output_stream.is_open()) {
    std::cerr << "failed to open file: " << filename << std::endl;
    return EXIT_FAILURE;
  }
  
  // write CSV header row
  output_stream << "Detector Type" << ","
                << "Descriptor Type" << ","
                << "Frame#" << ","
                << "#KeyPointsPerFrame" << ","
                << "#KeyPointsPerROI" << ","
                << "DetectorTime(ms)" << ","
                << "DescriptorTime(ms)" << ","
                << "#MatchedPoints" << "," << "MatchingTime(ms))" << std::endl;
  
  // write det/des performance data to .csv output file line by line
  for (const auto &combo : combinations) {
    for (int i = 0; i < 10; i++) {
      output_stream << combo.detectorType
                    << "," << combo.descriptorType
                    << "," << i
                    << "," << combo.numKeyPointsPerframe[i]
                    << "," << combo.numKeyPointsPerROI[i]
                    << "," << std::fixed << std::setprecision(8) << combo.detectorTime[i]
                    << "," << std::fixed << std::setprecision(8) << combo.descriptorTime[i]
                    << "," << combo.numMatchedKeyPoints[i]
                    << "," << std::fixed << std::setprecision(8) << combo.MatcherTime[i] << std::endl;
    }
    output_stream << std::endl;
  }
  
  output_stream.close();

  return EXIT_SUCCESS;
}