I created a horizontal swarmchart in app designer. The input data have numeric values and grouping tags (intGroups) associated with each point. Each point’s color is associated with its group. I also defined a ButtonDownFcn to get the point that the user clicks on (using code from a previous Matlab Answer).
The issue is that when I click a point, swarmchart’s XData and YData give the undithered coordinates (i.e., the y-values are all the same). So if I click a point that is far from center (due to a lot of points having that same value), the code below may or may not identify that point I clicked, so I may not get the correct group.
Is there a way to ensure that I get the exact point I clicked (or its index in the vector), not others that are in the same vicinity?
for zz = 1:length(intVarsUnique)
hPlot = swarmchart(axPlot, xData(:, zz), intVars(:, zz), [], categorical(strGroupColors), ‘filled’, ‘o’, …
‘YJitter’,’density’, …
‘HitTest’, ‘on’, ‘ButtonDownFcn’, @(src, eventData) fcnPlot_ButtonDown(app, src, eventData));
if ~ishold(axPlot)
hold(axPlot, ‘on’);
end
end % zz
hold(axPlot, ‘off’);

function fcnPlot_ButtonDown(app, hPlot, eventData)
% Based on code from Yair Altman in https://www.mathworks.com/matlabcentral/answers/1903190-get-data-point-that-was-clicked-on-in-graph
% Get the click coordinates from the click event data
x = eventData.IntersectionPoint(1);
y = eventData.IntersectionPoint(2);
line_xs = hPlot.XData;
line_ys = hPlot.YData;
dist2 = (x-line_xs).^2 + (y-line_ys).^2;
[~,min_idx] = min(dist2);
closest_x = line_xs(min_idx);
closest_y = line_ys(min_idx);
msgbox(sprintf(‘Clicked on: (%g,%g)nClosest pt: (%g,%g)’, x, y, closest_x, closest_y));
% Code to locate point in vector and ID group…
endI created a horizontal swarmchart in app designer. The input data have numeric values and grouping tags (intGroups) associated with each point. Each point’s color is associated with its group. I also defined a ButtonDownFcn to get the point that the user clicks on (using code from a previous Matlab Answer).
The issue is that when I click a point, swarmchart’s XData and YData give the undithered coordinates (i.e., the y-values are all the same). So if I click a point that is far from center (due to a lot of points having that same value), the code below may or may not identify that point I clicked, so I may not get the correct group.
Is there a way to ensure that I get the exact point I clicked (or its index in the vector), not others that are in the same vicinity?
for zz = 1:length(intVarsUnique)
hPlot = swarmchart(axPlot, xData(:, zz), intVars(:, zz), [], categorical(strGroupColors), ‘filled’, ‘o’, …
‘YJitter’,’density’, …
‘HitTest’, ‘on’, ‘ButtonDownFcn’, @(src, eventData) fcnPlot_ButtonDown(app, src, eventData));
if ~ishold(axPlot)
hold(axPlot, ‘on’);
end
end % zz
hold(axPlot, ‘off’);

function fcnPlot_ButtonDown(app, hPlot, eventData)
% Based on code from Yair Altman in https://www.mathworks.com/matlabcentral/answers/1903190-get-data-point-that-was-clicked-on-in-graph
% Get the click coordinates from the click event data
x = eventData.IntersectionPoint(1);
y = eventData.IntersectionPoint(2);
line_xs = hPlot.XData;
line_ys = hPlot.YData;
dist2 = (x-line_xs).^2 + (y-line_ys).^2;
[~,min_idx] = min(dist2);
closest_x = line_xs(min_idx);
closest_y = line_ys(min_idx);
msgbox(sprintf(‘Clicked on: (%g,%g)nClosest pt: (%g,%g)’, x, y, closest_x, closest_y));
% Code to locate point in vector and ID group…
end I created a horizontal swarmchart in app designer. The input data have numeric values and grouping tags (intGroups) associated with each point. Each point’s color is associated with its group. I also defined a ButtonDownFcn to get the point that the user clicks on (using code from a previous Matlab Answer).
The issue is that when I click a point, swarmchart’s XData and YData give the undithered coordinates (i.e., the y-values are all the same). So if I click a point that is far from center (due to a lot of points having that same value), the code below may or may not identify that point I clicked, so I may not get the correct group.
Is there a way to ensure that I get the exact point I clicked (or its index in the vector), not others that are in the same vicinity?
for zz = 1:length(intVarsUnique)
hPlot = swarmchart(axPlot, xData(:, zz), intVars(:, zz), [], categorical(strGroupColors), ‘filled’, ‘o’, …
‘YJitter’,’density’, …
‘HitTest’, ‘on’, ‘ButtonDownFcn’, @(src, eventData) fcnPlot_ButtonDown(app, src, eventData));
if ~ishold(axPlot)
hold(axPlot, ‘on’);
end
end % zz
hold(axPlot, ‘off’);

function fcnPlot_ButtonDown(app, hPlot, eventData)
% Based on code from Yair Altman in https://www.mathworks.com/matlabcentral/answers/1903190-get-data-point-that-was-clicked-on-in-graph
% Get the click coordinates from the click event data
x = eventData.IntersectionPoint(1);
y = eventData.IntersectionPoint(2);
line_xs = hPlot.XData;
line_ys = hPlot.YData;
dist2 = (x-line_xs).^2 + (y-line_ys).^2;
[~,min_idx] = min(dist2);
closest_x = line_xs(min_idx);
closest_y = line_ys(min_idx);
msgbox(sprintf(‘Clicked on: (%g,%g)nClosest pt: (%g,%g)’, x, y, closest_x, closest_y));
% Code to locate point in vector and ID group…
end matlab, swarmchart, appdesigner, undocumented MATLAB Answers — New Questions

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