c++ Eigen 入门学习

1. FILE * fp = NULL;

  fp = fopen("l1_check.txt", "wb+");


  for (auto frames = 0; frames <fileParse->frame_count; frames++)
  {
    Eigen::Quaternionf Qsensor2NED = {
      fileParse->quat_array_list[frames][3 * 4 + 0],
      fileParse->quat_array_list[frames][3 * 4 + 1],
      fileParse->quat_array_list[frames][3 * 4 + 2],
      fileParse->quat_array_list[frames][3 * 4 + 3],
    };


    Eigen::Vector3f accInSensor = {
      fileParse->acc_array_list[frames][3 * 3 + 0],
      fileParse->acc_array_list[frames][3 * 3 + 1],
      fileParse->acc_array_list[frames][3 * 3 + 2]
    };
    Eigen::Vector3f accInNED = Qsensor2NED.matrix() * accInSensor;/*
    cout << "frames:\t" << frames << endl;
    cout << accInNED.x() << "\t" << accInNED.y() << "\t" << accInNED.z() - 1 << endl;*/


    float mod = sqrt(accInNED.x() * accInNED.x() + accInNED.y() * accInNED.y() + (accInNED.z() - 1)*(accInNED.z() - 1));
    cout << "mod:\t" << mod << endl;
    fprintf(fp, "%d\t%f\t%f\t%f\t%f\n", frames, mod, accInNED.x(), accInNED.y(), accInNED.z() - 1);
  }
  fclose(fp);