matlab app uiaxes 设置一天竖直的线，输出竖直的线与曲线交点的坐标

以下是一个示例代码，可以实现在MATLAB App的uiaxes中绘制一条垂直线，并输出该线与曲线交点的坐标：

classdef MyApp < matlab.apps.AppBase

    % Properties that correspond to app components
    properties (Access = public)
        UIFigure        matlab.ui.Figure
        UIAxes          matlab.ui.control.UIAxes
    end

    % Callbacks that handle component events
    methods (Access = private)

        function UIAxesButtonDown(app, event)
            % 获取鼠标点击位置的x坐标
            xPos = event.IntersectionPoint(1);
            % 在UIAxes中绘制一条垂直线
            hold(app.UIAxes, 'on');
            line(app.UIAxes, [xPos xPos], ylim(app.UIAxes), 'Color', 'r');
            hold(app.UIAxes, 'off');
            % 计算线与曲线的交点
            xData = app.UIAxes.Children.XData;
            yData = app.UIAxes.Children.YData;
            [~, idx] = min(abs(xData-xPos));
            xIntersect = xData(idx);
            yIntersect = yData(idx);
            % 输出交点坐标
            disp(['Intersection at x = ', num2str(xIntersect), ', y = ', num2str(yIntersect)]);
        end

    end

    % App initialization and construction
    methods (Access = private)

        % Create UIFigure and components
        function createComponents(app)
            % Create UIFigure and configure properties
            app.UIFigure = uifigure('Name', 'My App');
            app.UIFigure.Position = [100 100 640 480];

            % Create UIAxes
            app.UIAxes = uiaxes(app.UIFigure);
            title(app.UIAxes, 'My Plot')
            xlabel(app.UIAxes, 'X')
            ylabel(app.UIAxes, 'Y')
            app.UIAxes.Position = [50 50 500 400];
            app.UIAxes.ButtonDownFcn = @app.UIAxesButtonDown;
        end
    end

    % App creation and deletion
    methods (Access = public)

        % Construct app
        function app = MyApp

            % Create and configure components
            createComponents(app)

            % Show the figure after all components are created
            app.UIFigure.Visible = 'on';
        end
    end
end

在此示例代码中，我们创建了一个名为`MyApp`的MATLAB App，并在UIAxes中绘制了一个曲线。当用户单击UIAxes时，我们获取鼠标点击位置的x坐标，并在UIAxes中绘制一条垂直线。然后，我们计算该线与曲线的交点，并输出交点坐标。您可以根据需要修改此示例代码以适应您的应用程序。