Link different data sources in Matlab subplots-CodePudding

The

However, if I toggle linkdata on, the plot completely changes to this.

How can I preserve the original plot while enabling linking them?

As a last remark: I would obviously want to call that function with arguments (lat, lon, x, y) later on. But for this MWE, I thought it would be easier this way.

CodePudding user response：

Interesting question. Rather than linkdata, a callback function that responds to a click input would be more natural to me.

The solution below is a quick hack -- you'd always need to select a point in subplot 1. It can be made more fancy by using MATLAB's ButtonDownFcn function and by defining a callback that understands which subplot has been selected.

close all clearvars t = linspace(-2,2,100); lat = sin(t); lon = cos(t); x = t; y = exp(t); M = [lat',lon',x',y']; figure(1); subplot(1,2,1) plot(M(:,1),M(:,2),'-x','XDataSource','M(:,1)','YDataSource','M(:,2)'); subplot(1,2,2) plot(M(:,3),M(:,4),'-x','XDataSource','M(:,3)','YDataSource','M(:,4)'); % Quick hack while 1 % Get coordinates of clicked point waitforbuttonpress; CP = get(gca,'CurrentPoint'); x1 = CP(2,1); % X-point y1 = CP(2,2); % Y-point % Find index of closest point dists = (M(:,1)-x1).^2 (M(:,2)-y1).^2; [~,idx] = min(dists); % Replot base-figure to remove previously selected points figure(1); subplot(1,2,1) plot(M(:,1),M(:,2),'-x','XDataSource','M(:,1)','YDataSource','M(:,2)'); subplot(1,2,2) plot(M(:,3),M(:,4),'-x','XDataSource','M(:,3)','YDataSource','M(:,4)'); % Update both subplots subplot(1,2,1) hold on plot(M(idx,1),M(idx,2),'ro'); hold off subplot(1,2,2) hold on plot(M(idx,3),M(idx,4),'ro'); hold off end

CodePudding user response：

You can use the undocumented BrushData property with Brush's ActionPostCallback. The 'BrushData' property is a uint8 array of 0s and 1s, with 1s indicating data points that are selected. In the callback function, set the BrushData of both subplots simultaneously when either of them is "brushed".

function linkedexample() t = linspace(-2,2,100); lat = sin(t); lon = cos(t); x = t; y = exp(t); fig=figure(); subplot(1,2,1) p1=plot(lat,lon); subplot(1,2,2) p2=plot(x,y); % Bind callback function with the brush b = brush(fig); b.ActionPostCallback = {@onBrushAction}; % callback function function onBrushAction(~,eventdata) set(p1, 'BrushData', eventdata.Axes.Children.BrushData) set(p2, 'BrushData', eventdata.Axes.Children.BrushData) end end

The result:

Accessing plot brushed data on "Undocumented Matlab" and this Mathwork post by its staff, provide more information of BrushData and ActionPostCallback.