I understand that you have a table “data” which consists of four columns, and you want to find the groups based on the columns "Indication", "Study-name" and "Sequence". After finding the groups you want to assign each row in “Pseudonym” to one of these groups.
After this, it is required to randomly pick “x” number of “Pseudonym” from all groups, keeping the group size in consideration.
I am attaching the code below which will randomly pick the “Pseudonym” from all groups while considering the group-size:
data1 = data(:, {'Indication', 'Study-name', 'Sequence'});
[p, v] = findgroups(data1);
groups = splitapply(@(x) {x}, data.Pseudonym, p);
numPicks = 20; % Number of pseudonyms to pick in total
pickedPseudonyms = [];
totalPseudonyms = sum(cellfun(@numel, groups));
scalingFactor = numPicks / totalPseudonyms;
[~, sortedIndices] = sort(cellfun(@numel, groups), 'descend');
sortedGroups = groups(sortedIndices);
for i = 1:numel(sortedGroups)
groupSize = numel(sortedGroups{i});
picksFromGroup = round(groupSize * scalingFactor); % Adjust picks based on group size
if picksFromGroup > 0
randomIndices = randperm(groupSize, min(groupSize, picksFromGroup));
pickedPseudonyms = [pickedPseudonyms, sortedGroups{i}(randomIndices)];
end
% Break the loop if 20 pseudonyms are selected
if numel(pickedPseudonyms) >= numPicks
break;
end
end
You can also refer to the MATLAB documentation for "randperm" to obtain more information on its usage and syntax. The link is provided below: -
I hope this helps!
