如何实现换行显示def getActors(filename): actors = dict() # 打开xlsx文件，并获取第一个worksheet wb = openpyxl.load_workbook((filename)) ws = wb.worksheets[0] # 遍历Excel文件中的所有文件中的所有行 for index, row in enumerate(ws.rows): # 跳过第一行的表头 if index == 0: continue # 获取电影名称和演员列表 fileName, actor = row[0].value, row[1].value.split('/') # 遍历该电影所有演员，统计参演电影 for a in actor: actors[a] = actors.get(a, set()) actors[a].add(fileName) return actors data = getActors('实践2素材.xlsx') print(data)

可以参考以下代码实现： ```cpp #include "mainwindow.h" #include "ui_mainwindow.h" #include <iostream> #include <fstream> #include <string> #include <vector> #include <cmath> #include <QFileDialog> #include <QMessageBox> #include <pcl/point_types.h> #include <pcl/io/pcd_io.h> #include <pcl/visualization/pcl_visualizer.h> typedef pcl::PointXYZ PointT; typedef pcl::PointCloud<PointT> PointCloudT; MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow) { ui->setupUi(this); //连接信号与槽函数 connect(ui->actionOpen, SIGNAL(triggered(bool)), this, SLOT(openFile())); connect(ui->pushButton, SIGNAL(clicked(bool)), this, SLOT(DBH())); } MainWindow::~MainWindow() { delete ui; } void MainWindow::openFile() { QString fileName = QFileDialog::getOpenFileName(this, tr("Open Point Cloud"), "", tr("Point Cloud Files (*.pcd *.txt)")); if(!fileName.isEmpty()) { //清空界面 ui->qvtkWidget->update(); ui->textBrowser->clear(); //读取点云文件 pcl::PointCloud<pcl::PointXYZ>::Ptr cloud(new pcl::PointCloud<pcl::PointXYZ>); if (pcl::io::loadPCDFile<pcl::PointXYZ>(fileName.toStdString(), *cloud) == -1) { //尝试读取txt格式文件 std::ifstream ifs(fileName.toStdString()); if (!ifs.is_open()) { QMessageBox::critical(this, "Error", "Cannot open file!"); return; } std::string line; while (std::getline(ifs, line)) { pcl::PointXYZ p; std::stringstream ss(line); ss >> p.x >> p.y >> p.z; cloud->push_back(p); } ifs.close(); } //显示点云 pcl::visualization::PCLVisualizer vis("Point Cloud"); vis.setBackgroundColor(0.0, 0.0, 0.0); vis.addPointCloud(cloud, "cloud"); vis.setPointCloudRenderingProperties(pcl::visualization::PCL_VISUALIZER_POINT_SIZE, 1, "cloud"); ui->qvtkWidget->update(); //输出点云信息 std::stringstream ss; ss << "Number of points: " << cloud->size() << std::endl; ui->textBrowser->append(ss.str().c_str()); //保存点云 cloud_ = cloud; } } void MainWindow::DBH() { if (!cloud_) { QMessageBox::warning(this, "Warning", "No point cloud selected!"); return; } //获取选中的点 std::vector<int> indices; if (ui->qvtkWidget->getRenderWindow()->GetRenderers()->GetFirstRenderer()->GetViewProp("cloud")) { vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New(); actor = ui->qvtkWidget->getRenderWindow()->GetRenderers()->GetFirstRenderer()->GetActors()->GetLastActor(); vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New(); mapper = vtkPolyDataMapper::SafeDownCast(actor->GetMapper()); vtkSmartPointer<vtkDataSet> dataSet = vtkSmartPointer<vtkDataSet>::New(); dataSet = mapper->GetInput(); vtkSmartPointer<vtkUnsignedCharArray> pointColors = vtkSmartPointer<vtkUnsignedCharArray>::New(); pointColors = vtkUnsignedCharArray::SafeDownCast(dataSet->GetPointData()->GetScalars()); for (vtkIdType i = 0; i < pointColors->GetNumberOfTuples(); i++) { if (pointColors->GetValue(i) == 255) { indices.push_back(i); } } } if (indices.empty()) { QMessageBox::warning(this, "Warning", "No point selected!"); return; } //计算胸径 double sum_x = 0.0, sum_y = 0.0, sum_z = 0.0, sum_xy = 0.0, sum_xz = 0.0, sum_xx = 0.0; for (int i : indices) { sum_x += cloud_->points[i].x; sum_y += cloud_->points[i].y; sum_z += cloud_->points[i].z; sum_xx += cloud_->points[i].x * cloud_->points[i].x; sum_xy += cloud_->points[i].x * cloud_->points[i].y; sum_xz += cloud_->points[i].x * cloud_->points[i].z; } double n = static_cast<double>(indices.size()); double a = (n * sum_xy - sum_x * sum_y) / (n * sum_xx - sum_x * sum_x); double b = (sum_y - a * sum_x) / n; double c = (n * sum_xz - sum_x * sum_z) / (n * sum_xx - sum_x * sum_x); double d = (sum_z - c * sum_x) / n; double D = 2.0 * sqrt(a * a + 1) * 1000.0; //单位：毫米 //输出胸径 std::stringstream ss; ss << "DBH: " << D << " mm" << std::endl; ui->textBrowser->append(ss.str().c_str()); } ``` 该函数基于最小二乘法，通过获取当前选中的实体作为点云文件来源，实现对txt格式的树木点云文件的胸径计算。

创建一个电影类，我们可以参考豆瓣电影的信息结构。例如，可以考虑以下属性：电影ID、标题、导演、演员、评分、上映年份和简介。为了保护这些信息不直接暴露在外，我们将它们设置为私有变量，并提供公有的getter方法来获取这些数据。 ```java public class Movie { // 私有属性 private int movieId; private String title; private String director; private String[] actors; private double rating; private int year; private String summary; // 构造函数 public Movie(int movieId, String title, String director, String[] actors, double rating, int year, String summary) { this.movieId = movieId; this.title = title; this.director = director; this.actors = actors; this.rating = rating; this.year = year; this.summary = summary; } // 公共方法获取私有属性 public int getMovieId() { return movieId; } public String getTitle() { return title; } public String getDirector() { return director; } public String[] getActors() { return actors; } public double getRating() { return rating; } public int getYear() { return year; } public String getSummary() { return summary; } // 示例：创建并初始化电影对象 public static void main(String[] args) { String[] actors = {"张三", "李四"}; Movie film = new Movie(35242872, "肖申克的救赎", "弗兰克·德拉邦特", actors, 9.6, 1994, "两个男人在监狱中的友情故事"); System.out.println("电影ID: " + film.getMovieId()); System.out.println("标题: " + film.getTitle()); System.out.println("导演: " + film.getDirector()); System.out.println("主演: " + Arrays.toString(film.getActors())); System.out.println("评分: " + film.getRating()); System.out.println("上映年份: " + film.getYear()); System.out.println("简介: " + film.getSummary()); } } ```