how do i extract 3 separate groups from one column

How do i extract 3 groups from one coloumn in association to their mean e.g:

group mean

1 24

1 34

2 60

2 12

3 14

3 12

How do i extract the data from each group separately and plot

[Savannah Britto]

Any help is appreciated !!!

Answer 1

[Image Analyst]

Try this:

groupMean = [...
1              24
1              34
2              60
2              12
3             14
3             12];
uniqueGroups = unique(groupMean(:, 1))

uniqueGroups = 3×1

1 2 3

for g = 1 : length(uniqueGroups)
	thisGroup = uniqueGroups(g);
	thisGroupsRows = groupMean(:, 1) == thisGroup;
	theseMeans = groupMean(thisGroupsRows, 2); % Get value in column 2
% 	bar(theseMeans);
	plot(theseMeans, '.-', 'LineWidth', 2, 'MarkerSize', 40)
	hold on;
	legendStrings{g} = sprintf('Group %d', thisGroup);
end
grid on;
legend(legendStrings)

[Savannah Britto]

THjank you. i ran the data but there is an error message of this line: theseMeans = groupMean(thisGroupsRows, 2); % Get value in column 2

[Image Analyst]

Show your code, because as you can see I literally ran it in the text box above and it ran fine. Maybe you don't have a matrix. Maybe you have a table - I don't know because you forgot to attach the actual data. So I don't know the exact type of variable(s) they are. Attach your matrix if you still have trouble.

[Savannah Britto]

[Image Analyst]

@Savannah Britto I'm not sure how you adapted my code since you forgot to attach it. However it seems to work fine for me with no error:

% subj	group	trial	logmIKI
data = readmatrix('advancedstats2.csv');
groupNumbers = data(:, 2);
logmIKI = data(:, 4);
uniqueGroups = unique(groupNumbers)
for g = 1 : length(uniqueGroups)
    % Get the group we'll use on this iteration.
    thisGroup = uniqueGroups(g);
    % Find out what rows this group number appears in.
    thisGroupsRows = groupNumbers == thisGroup;
    % Get logmIKI value.
    theseMeans = logmIKI(thisGroupsRows); 
    % 	bar(theseMeans);
    plot(theseMeans, '-', 'LineWidth', 2)
    hold on;
    legendStrings{g} = sprintf('Group %d', thisGroup);
end
grid on;
legend(legendStrings)

Of course each group has different number of elements, and since I'm plotting the x value as just the index, the plots have different widths in the x direction.

[Savannah Britto]

thank you!

[Image Analyst]

You didn't click "Accept this answer" so I'm wondering what's left undone? Did my code not do what you expected?