matlab gui的数学图

Question

我需要在Matlab中创建一个GUI,使我能够以交互方式绘制图形,并给出边和顶点的值.

然后我需要返回边的这些值(x,y,value)和顶点的(x1,y1,x2,y2,value).

不幸的是,我甚至不知道从哪里开始.我创建了一个gui,让我用两种不同的方法交互式地绘制线条,但我不知道如何继续.请帮忙.

Answer 1

您始终可以处理鼠标事件以启用交互式绘图.我花了一些时间在这上面并提出了以下GUI.

function interactive_graph_gui
    % data
    showLabels = false;   % flag to determine whether to show node labels
    prevIdx = [];         % keeps track of 1st node clicked in creating edges
    selectIdx = [];       % used to highlight node selected in listbox
    pts = zeros(0,2);     % x/y coordinates of vertices
    adj = sparse([]);     % sparse adjacency matrix (undirected)

    % create GUI
    h = initGUI();

    function h = initGUI()
        h.fig = figure('Name','Interactive Graph', 'Resize','off');
        h.ax = axes('Parent',h.fig, 'ButtonDownFcn',@onMouseDown, ...
            'XLim',[0 1], 'YLim',[0 1], 'XTick',[], 'YTick',[], 'Box','on', ...
            'Units','pixels', 'Position',[160 20 380 380]);

        h.list = uicontrol('Style','listbox', 'Parent',h.fig, 'String',{}, ...
            'Min',1, 'Max',1, 'Value',1, ...
            'Position',[20 80 130 320], 'Callback',@onSelect);
        uicontrol('Style','pushbutton', 'Parent',h.fig, 'String','Clear', ...
            'Position',[20 20 60 20], 'Callback',@onClear);
        uicontrol('Style','pushbutton', 'Parent',h.fig, 'String','Export', ...
            'Position',[90 20 60 20], 'Callback',@onExport);
        uicontrol('Style','pushbutton', 'Parent',h.fig, 'String','Delete', ...
            'Position',[50 50 60 20], 'Callback',@onDelete);

        h.cmenu = uicontextmenu('Parent',h.fig);
        h.menu = uimenu(h.cmenu, 'Label','Show labels', 'Checked','off', ...
            'Callback',@onCMenu);
        set(h.list, 'UIContextMenu',h.cmenu)

        h.pts = line(NaN, NaN, 'Parent',h.ax, 'HitTest','off', ...
            'Marker','o', 'MarkerSize',10, 'MarkerFaceColor','b', ...
            'LineStyle','none');
        h.selected = line(NaN, NaN, 'Parent',h.ax, 'HitTest','off', ...
            'Marker','o', 'MarkerSize',10, 'MarkerFaceColor','y', ...
            'LineStyle','none');
        h.prev = line(NaN, NaN, 'Parent',h.ax, 'HitTest','off', ...
            'Marker','o', 'MarkerSize',20, 'Color','r', ...
            'LineStyle','none', 'LineWidth',2);
        h.edges = line(NaN, NaN, 'Parent',h.ax, 'HitTest','off', ...
            'LineWidth',2, 'Color','g');
        h.txt = [];

    end

    function onMouseDown(~,~)
        % get location of mouse click (in data coordinates)
        p = get(h.ax, 'CurrentPoint');

        % determine whether normal left click was used or otherwise
        if strcmpi(get(h.fig,'SelectionType'), 'Normal')
            % add a new node
            pts(end+1,:) = p(1,1:2);
            adj(end+1,end+1) = 0;
        else
            % add a new edge (requires at least 2 nodes)
            if size(pts,1) < 2, return; end

            % hit test (find node closest to click location: euclidean distnce)
            [dst,idx] = min(sum(bsxfun(@minus, pts, p(1,1:2)).^2,2));
            if sqrt(dst) > 0.025, return; end

            if isempty(prevIdx)
                % starting node (requires a second click to finish)
                prevIdx = idx;
            else
                % add the new edge
                adj(prevIdx,idx) = 1;
                prevIdx = [];
            end
        end

        % update GUI
        selectIdx = [];
        redraw()
    end

    function onDelete(~,~)
        % check that list of nodes is not empty
        if isempty(pts), return; end

        % delete selected node
        idx = get(h.list, 'Value');        
        pts(idx,:) = [];
        adj(:,idx) = [];
        adj(idx,:) = [];

        % clear previous selections
        if prevIdx == idx
            prevIdx = [];
        end
        selectIdx = [];

        % update GUI
        set(h.list, 'Value',max(min(idx,size(pts,1)),1))
        redraw()
    end

    function onClear(~,~)
        % reset everything
        prevIdx = [];
        selectIdx = [];
        pts = zeros(0,2);
        adj = sparse([]);

        % update GUI
        set(h.list, 'Value',1)
        redraw()
    end

    function onExport(~,~)
        % export nodes and adjacency matrix to base workspace
        assignin('base', 'adj',(adj+adj')>0)  % make it symmetric
        assignin('base', 'xy',pts)
    end

    function onSelect(~,~)
        % update index of currently selected node
        selectIdx = get(h.list, 'Value');
        redraw()
    end

    function onCMenu(~,~)
        % flip state
        showLabels = ~showLabels;
        redraw()
    end

    function redraw()
        % edges
        p = nan(3*nnz(adj),2);
        [i,j] = find(adj);
        p(1:3:end,:) = pts(i,:);
        p(2:3:end,:) = pts(j,:);
        set(h.edges, 'XData',p(:,1), 'YData',p(:,2))

        % nodes
        set(h.pts, 'XData',pts(:,1), 'YData',pts(:,2))
        set(h.prev, 'XData',pts(prevIdx,1), 'YData',pts(prevIdx,2))
        set(h.selected, 'XData',pts(selectIdx,1), 'YData',pts(selectIdx,2))

        % list of nodes
        set(h.list, 'String',num2str(pts,'(%.3f,%.3f)'))

        % node labels
        if ishghandle(h.txt), delete(h.txt); end
        if showLabels
            set(h.menu, 'Checked','on')
            h.txt = text(pts(:,1)+0.01, pts(:,2)+0.01, ...
                num2str((1:size(pts,1))'), ...
                'HitTest','off', 'FontSize',8, ...
                'VerticalAlign','bottom', 'HorizontalAlign','left');
        else
            set(h.menu, 'Checked','off')
        end

        % force refresh
        drawnow
    end

end

这一切都归结为处理轴对象的ButtonDownFcn回调,并使用CurrentPoint属性查询最后一次鼠标单击的位置.

以下列出了与GUI交互的可能方法:

• 在轴内左键单击以创建顶点
• 右键单击两个节点以创建边缘
• 使用列表框选择并突出显示节点.使用"删除"按钮删除选定的顶点.
• "清除"按钮可以重置所有内容

• "导出"按钮在基础工作空间中创建两个变量,包含顶点2D坐标(N×2矩阵)和边(作为稀疏N×N矩阵).您可以照常将这些变量与其他图形函数一起使用:

  gplot(adj, xy, 'b.-')
  

• 最后,您可以右键单击列表框.这将弹出一个弹出菜单,其中包含显示顶点标签的选项.

您可以扩展上面的代码以将值赋给顶点.例如,您可以使用列表框的回调函数为顶点指定值(当用户从​​列表中选择一个项目时显示输入对话框).您还可以使用与处理ButtonDownFcn回调相同的技术.类似地,您可以创建第二个列表框来显示边缘并以相同的方式处理值的赋值...我将那部分给你:)