When creating a swarmchart from categorical X and double Y values, is there a way to extract the resulting jittered X values?

s = random_swarms(2^10);

jitteredXvals = [] % WHAT GOES HERE?

jitteredXvals =

     []

function [s, x, y] = random_swarms(n)
% Input:
%   n: number of data points
% Outputs:
%   s: handle to the swarmchart
%   x: categorical variable ('A' or 'B')
%   y: random numbers

% Generate random categorized values
categories = {'A', 'B'};
x = categorical(categories(randi(2, n, 1)));
y = randn(n, 1);

% Create swarmchart
s = swarmchart(x, y);

% Set title and labels
title('Random Swarmchart')
xlabel('Category')
ylabel('Random Value')
end

[Adam Danz]

> is there a way to extract the resulting jittered X values?

No, there isn't. The shape of the jittered values is formed by the kernel density estimate computed by kde.

How do you plan to use the (x,y) coordinates of the scatter points? Perhaps I could help you find a workaround learn from your use case.

[Jim]

I want to be able to interact with that graph "intelligently" in certain ways that are made easier by knowing where the points are. The response below got me what I needed.

[Adam Danz]

If I were to make a case to document the solution @Walter Roberson shared, it would be helpful to have a more detailed use case, if you don't mind sharing.

[Jim]

One straightforward use case is to move those values into another program, such as Excel, where generating a nicely jittered graph is a PITA.

The one I am actually experimenting with involves drawing a "cutoff" at different levels of the "cloud" and having it expand and shrink as it moves up and down—purely aesthetic.

Additionally, what if I want to identify a specific point or set of points in that graph for some reason and highlight it somehow? I would need to know where the points of interest are actually plotted to do so.

[Adam Danz]

Thanks for the additional details.

Answer 1

[Walter Roberson]

ss = struct(s);
ss.XYZJittered

Note: the default setting for swarmchart is Jitter = 'off'

[Jim]

I love the warning it gives:

Warning: Calling STRUCT on an object prevents the object from hiding its implementation details and should thus be avoided. Use DISP or DISPLAY to see the visible public details of an object. See 'help struct' for more information.

It's like...don't do this! But yup, that works!

Thanks!