User selected points from a plot

I need to visually inspect a certain metric and select the points that are good. I have something that works but it seems like there should be a better way to do this. My main issue is that the only functions I found selected a random spot on the axes and I would like to limit it to only selecting data points. I wrote a solution but it won't work with tightly spaced data points.

Is there a better way for a user to select points from a plot?

Code Below:

function [TotalImage,Points] = PickPeakImages(Struct);
%% Struct(1) is an NxNxi image array
% Struct(2) is time informations for each image
% Struct(5) is a measured value for each image


FN = fieldnames(Struct);
l = length(FN);

TotalImage = [];
Points = [];
f = figure;
title('Select Points then Press Enter')
for Si = 1:l
    plot(Struct(2).(FN{Si}),Struct(5).(FN{Si}))
    title('Select Points then Press Enter')
    [x,~] = getpts(f);  % I would like to select points from a plot and this is the closest I could find.
    Points = cat(1,Points,x);
    for xi = 1:length(x)
        ImageIndex = (abs(Struct(2).(FN{Si}) - x(xi)) == min(abs(Struct(2).(FN{Si}) - x(xi))));  % Can't select a point from the plot itself so this gets the right index. It's ok for this purpose but really slow.
        TotalImage = cat(3,TotalImage,Struct(1).(FN{Si})(:,:,ImageIndex));
    end
end

close(f)

Answer 1

[Geoff Hayes]

Kyle - from https://www.mathworks.com/matlabcentral/answers/11439-selecting-data-from-a-plot-in-a-gui, there is an answer that suggests using brush. Sample code that allow the user to pick (in this case 4) sets of data is as follows;

function [selectedXData, selectedYData] = DataPickerExample

    close all;

    % create some test data and plot it
    x = -2*pi:0.1:2*pi;
    y = sin(x);
    hFig = figure;
    hPlot = plot(x,y);
    
    % create and enable the brush object
    hBrush = brush(hFig);
    hBrush.ActionPostCallback = @OnBrushActionPostCallback;
    hBrush.Enable = 'on';
    
    selectedXData = [];
    selectedYData = [];
    
    % select 4 sets of data points
    for x=1:4
        fprintf('select some points.\n');
        uiwait;
    end
    
    % turn off the brush
    hBrush.Enable = 'off';

    function OnBrushActionPostCallback(~, ~)
       
        xData = hPlot.XData;
        yData = hPlot.YData;
        brushedDataIndices = hPlot.BrushData;

        selectedXData = [selectedXData xData(logical(brushedDataIndices))];
        selectedYData = [selectedYData yData(logical(brushedDataIndices))];
        
        uiresume;
    end

end

[Kyle Wilkin]

Thanks! With a bit of tweaking I think this will work well.