读取如下内容：

[INFO] [2023927 13:23:04.303] [estimator.cpp:1894]: XYZI: 1.70492 -1.33857 1.99379 134
[INFO] [2023927 13:23:04.303] [estimator.cpp:1894]: XYZI: 1.70944 -1.32323 1.99325 125
[INFO] [2023927 13:23:04.303] [estimator.cpp:1892]: 1695792183.950074.pcd 
[INFO] [2023927 13:23:04.303] [estimator.cpp:1894]: XYZI: 1.69904 -1.3083 1.99324 142
[INFO] [2023927 13:23:04.303] [estimator.cpp:1894]: XYZI: 1.70866 -1.29287 1.99253 140
[INFO] [2023927 13:23:04.304] [estimator.cpp:1894]: XYZI: 1.71834 -1.2775 1.99181 138
[INFO] [2023927 13:23:04.304] [estimator.cpp:388]: Trailer angle estimator init success [INFO] [2023927 13:23:04.304] [estimator.cpp:312]: last_angle: 1695792184.150050 0.000625
[INFO] [2023927 13:23:04.353] [estimator.cpp:1941]: vehicle_pose: 1695792184.158000  -1456.254047 34.195933 93.047454
[INFO] [2023927 13:23:04.353] [estimator.cpp:1969]: trailer_pose: 1695792184.150050 34.231745
[INFO] [2023927 13:23:04.408] [estimator.cpp:475]: filter_angle: 1695792184.250059 0.000680
[INFO] [2023927 13:23:04.408] [estimator.cpp:490]: predict_angle: 1695792184.250059 0.000289
[INFO] [2023927 13:23:04.408] [estimator.cpp:352]: trailer_angle: 910 0.016561

解析出角度值 “filter_angle”， “predict_angle”，“trailer_angle”，并将结果保存成txt文档。
解析出XYZI: 1.70866 -1.29287 1.99253 140，并将结果按照解析出的“1695792183.950074.pcd ”来保存。

#include <dirent.h>
#include <fstream>
#include <iostream>
#include <pcl/io/pcd_io.h>
#include <pcl/point_cloud.h>
#include <sstream> //istringstream 必须包含这个头文件
#include <stdlib.h>
#include <string>
#include <vector>
using namespace std;struct angle_struct {double timestamp;double angle;
};struct point_struct {std::string pcd_name;double x;double y;double z;double i;
};void Stringsplit(const std::string str, const char split,std::vector<std::string> &res) {std::istringstream iss(str);std::string token;while (getline(iss, token, split)) {res.push_back(token);}
}
// 1695792261.850105.pcdvoid test(std::string &input_path) {ifstream ifs(input_path); //读取文件if (!ifs.good()) {cerr << "ifstream open file error!\n";return;}std::vector<std::vector<point_struct>> pcds;string line;// vector<string> lines;std::string get_pcd_name;point_struct point0;std::vector<point_struct> points_init;std::vector<angle_struct> trailer_angle;std::vector<angle_struct> predict_angle;std::vector<angle_struct> filter_angle;int count = 0;while (getline(ifs, line)) //获取每一行数据{//按照空格分// lines.push_back(line); //将每一行依次存入到vector中// cout << line << endl;  //顺便打印一下这一行std::vector<std::string> str_list;point_struct point;std::vector<point_struct> points;//----angle_struct angle_value;//按照空格将每一行内容划分为不同字符串，将每个字符串保存到vector里，此时每个vcetor保存这一行的内容Stringsplit(line, ' ', str_list);if (str_list.size() > 5) {string str_list_4 = str_list[4];if (str_list_4 == "XYZI:") {// std::cout << "XYZI: " << str_list[5] << " " << str_list[6] << " "//           << str_list[7] << " " << str_list[8] << std::endl;point.x = stod(str_list[5]);point.y = stod(str_list[6]);point.z = stod(str_list[7]);point.i = stod(str_list[8]);point.pcd_name = get_pcd_name;pcds.back().push_back(point);}}if (str_list.size() == 5) {get_pcd_name = str_list[4];pcds.push_back(points);count++;}if (str_list.size() == 7) {string ang_str = str_list[4];if (ang_str == "trailer_angle:") {angle_value.timestamp = stod(str_list[5]);angle_value.angle = stod(str_list[6]);trailer_angle.push_back(angle_value);}if (ang_str == "predict_angle:") {angle_value.timestamp = stod(str_list[5]);angle_value.angle = stod(str_list[6]);predict_angle.push_back(angle_value);}if (ang_str == "filter_angle:") {angle_value.timestamp = stod(str_list[5]);angle_value.angle = stod(str_list[6]);filter_angle.push_back(angle_value);}}else {continue;}}ifs.close();std::cout << "pcds: " << pcds.size() << std::endl;std::cout << "count: " << count << std::endl;for (int i = 0; i < pcds.size(); i++) {pcl::PointCloud<pcl::PointXYZINormal>::Ptr single_cloud(new pcl::PointCloud<pcl::PointXYZINormal>);std::string _name;//保存成每一帧点云single_cloud->width = 1;single_cloud->height = pcds[i].size();for (int j = 0; j < pcds[i].size(); j++) {pcl::PointXYZINormal Point;_name = pcds[i][j].pcd_name;Point.x = pcds[i][j].x;Point.y = pcds[i][j].y;Point.z = pcds[i][j].z;Point.intensity = pcds[i][j].i;single_cloud->points.push_back(Point);std::cout << "XYZI: " << pcds[i][j].pcd_name << " " << pcds[i][j].x << " "<< pcds[i][j].y << " " << pcds[i][j].z << " " << pcds[i][j].i<< std::endl;}//保存单帧pcdstd::string path_save = "../JTG/pcds/" + _name;std::cout << "path_save : " << path_save << std::endl;if (single_cloud->points.size() > 0) {pcl::io::savePCDFileBinaryCompressed(path_save,*single_cloud); //压缩保存}}ofstream ofs1("../JTG/trailer_angle.txt"); //把内容输出到a.txt文件中if (!ofs1.good()) {cerr << "ofstream open file error!\n";return;}for (auto &data : trailer_angle) {ofs1 << std::fixed << data.timestamp << " " << data.angle << '\n';}ofs1.close();//---------ofstream ofs2("../JTG/predict_angle.txt"); //把内容输出到a.txt文件中if (!ofs2.good()) {cerr << "ofstream open file error!\n";return;}for (auto &data : predict_angle) {ofs2 << std::fixed << data.timestamp << " " << data.angle << '\n';}ofs2.close();//------ofstream ofs3("../JTG/filter_angle.txt"); //把内容输出到a.txt文件中if (!ofs3.good()) {cerr << "ofstream open file error!\n";return;}for (auto &data : filter_angle) {ofs3 << std::fixed << data.timestamp << " " << data.angle << '\n';}ofs3.close();//-------
}int test2() {ofstream ofs("china_daily.txt", std::ios::app); //在文档中添加字符串if (!ofs) {cerr << "ofstream error!" << endl;return -1;}cout << ofs.tellp() << endl;    //输出整个文件的长度ofs << "this new line" << endl; //在文件末尾追加“this new line”ofs.close();return 0;
}int main(void) {std::string input_path ="../JTG/uto_trailer_pose_estimator_185511_1695792081229.txt";test(input_path);// test2();return 0;
}

Cmakelist文件如下：

cmake_minimum_required(VERSION 2.6)
project(main)set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED ON)find_package(PCL 1.8 REQUIRED)include_directories(${PCL_INCLUDE_DIRS})
link_directories(${PCL_LIBRARY_DIRS})
add_definitions(${PCL_DEFINITIONS})add_executable(main main.cpp)target_link_libraries (main ${PCL_LIBRARIES})