Matlab: How to save multiple variable points from mouse click (with 'ButtonDownFcn') from-CodePudding

I have a figure with some vertical lines added, as such:

figure
x = rand(1,41);
y = 1:41;
H(1)= plot(x,y,'r.');
H(2)= line([x(21) x(21)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');
H(3)= line([x(3) x(3)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');
H(4)= line([x(15) x(15)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');

I would like to be able to click on the lines with the mouse button, and store each of the clicked line index. The following script works but I don't know how to store each index in an array. The 'IndInWorkSpace' keeps changing for each click.

set(H, 'ButtonDownFcn', {@LineSelected, H})

function [indices] = LineSelected(ObjectH, H)
   set(ObjectH, 'LineWidth', 4);
   set(H(H ~= ObjectH), 'LineWidth', 2);
   % Get x and y data of the highlighted lines 
   ind = ObjectH.XData
   assignin('base','IndInWorkSpace',ind);
end

Any help will be much appreciated! Thank you!

CodePudding user response：

An easy fix is to first check if there was already an index found in the base workspace. If there already is a variable IndInWorkSpace, append to it, otherwise assign a new variable.

function LineSelected(ObjectH, H)
    set(ObjectH, 'LineWidth', 4);
    set(H(H ~= ObjectH), 'LineWidth', 2);
    % Get x and y data of the highlighted lines
    ind = ObjectH.XData;
    if evalin('base','exist(''IndInWorkSpace'',''var'')')
        indArray = evalin('base','IndInWorkSpace');
        indArray(end 1) = ind;
    else 
        indArray = ind;
    end 
    assignin('base', 'IndInWorkSpace', indArray);
end