如何在数据光标模式下更改双 y 轴和单 x 轴图的输出文本

Question

我有以下代码：

datee = {'23-10-201511:36:24', '23-10-201511:37:24', '23-10-201511:38:24', '23-10-201511:39:24', '23-10-201511:40:24', '23-10-201511:41:24', '23-10-201511:42:24', '23-10-201511:43:24', '23-10-201511:44:24', '23-10-201511:45:24'};
Temperature = [23.6, 23.6, 23.7, 23.7, 23.7, 23.7, 23.7, 23.7, 23.7, 23.7];
Humidity = [40, 40, 40, 39.9, 39.8, 39.7, 39.8, 39.8, 39.8, 39.8];
C = datenum(datee,'dd-mm-yyyyHH:MM:SS'); 
[ax,h1,h2] = plotyy(C,Temperature,C,Humidity)
hold on;
datestr(C); 
datetick(ax(1),'x','HH:MM','keepticks');
datetick(ax(2),'x','HH:MM','keepticks');
xlabel('time [hours]');
ylabel(ax(1),'Temperature [°C]');
ylabel(ax(2),'Humidity [%rH]');



dcm_obj = datacursormode(gcf); 
set(dcm_obj,'UpdateFcn',@myfunction);

function [output_txt] = myfunction(~,event_obj)
% Display the position of the data cursor
% obj          Currently not used (empty)
% event_obj    Handle to event object
% output_txt   Data cursor text string (string or cell array of strings).


pos = get(event_obj,'Position');


output_txt= {['time: ', datestr(pos(1))],...                           
    ['Temperature: ',num2str(pos(2),4)]};

 output_txt= {['time: ', datestr(pos(1))],...                           
    ['Humidity: ',num2str(pos(2),4)]};

If there is a Z-coordinate in the position, display it as well
if length(pos) > 2
output_txt{end+1} = ['Z: ',num2str(pos(3),4)];
end

如果我使用此代码，我只会看到两个 y 轴的 time 和 temperature 变量，但看不到湿度变量。

我想看到类似的东西，如果我点击一个 y 轴，它必须显示 time 和 temperature，对于其他 y 轴，time 和 humidity.

Answer 1

如果我对您的问题的解释正确，您希望根据所点击的行获得不同的数据提示。完成此操作的一种方法是将 event_obj 的 Target 与 plotyy:

返回的行对象的句柄进行比较

function testcode
datee = {'23-10-201511:36:24', '23-10-201511:37:24', '23-10-201511:38:24', '23-10-201511:39:24', '23-10-201511:40:24', '23-10-201511:41:24', '23-10-201511:42:24', '23-10-201511:43:24', '23-10-201511:44:24', '23-10-201511:45:24'};
Temperature = [23.6, 23.6, 23.7, 23.7, 23.7, 23.7, 23.7, 23.7, 23.7, 23.7];
Humidity = [40, 40, 40, 39.9, 39.8, 39.7, 39.8, 39.8, 39.8, 39.8];
C = datenum(datee,'dd-mm-yyyyHH:MM:SS');
[ax,h1,h2] = plotyy(C,Temperature,C,Humidity);
hold on;
datestr(C);
datetick(ax(1),'x','HH:MM','keepticks');
datetick(ax(2),'x','HH:MM','keepticks');
xlabel('time [hours]');
ylabel(ax(1),'Temperature [°C]');
ylabel(ax(2),'Humidity [%rH]');


dcm_obj = datacursormode(gcf);
set(dcm_obj,'UpdateFcn',{@myfunction, [h1, h2]});
end

function [output_txt] = myfunction(~,event_obj, linehandles)
% Display the position of the data cursor
% obj          Currently not used (empty)
% event_obj    Handle to event object
% output_txt   Data cursor text string (string or cell array of strings).

pos = get(event_obj,'Position');
targetline = get(event_obj, 'Target');

switch targetline
    case linehandles(1)
        output_txt = {['Time: ', datestr(pos(1))], ...
            ['Temperature: ',num2str(pos(2),4)] ...
            };
    case linehandles(2)
        output_txt = {['Time: ', datestr(pos(1))], ...
            ['Humidity: ',num2str(pos(2),4)] ...
            };
    otherwise
        % No match
        output_txt = {['X: ', datestr(pos(1))], ...
            ['Y: ',num2str(pos(2),4)] ...
            };
end

% If there is a Z-coordinate in the position, display it as well
if length(pos) > 2
    output_txt{end+1} = ['Z: ',num2str(pos(3),4)];
end
end

此处有两个主要变化：我已将 h1 和 h2 传递给您的回调以与 case-switch statement I added. You can use an equivalent if-else 语句一起使用，但我个人认为 case-switch 更优雅。

以及相应的数据提示：

如何在数据光标模式下更改双 y 轴和单 x 轴图的输出文本

How to change output text in datacursor mode for a plot with double y-axis with single x-axis

matlab

image-processing

plot

handles