extract data with unique ID

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sensation
sensation on 30 Oct 2019
Commented: sensation on 31 Oct 2019
Hi,
I have already read a lot regarding accumarray and examples but still struggling with this one.
I have data of 1500*19 columns where in the column e.g. 14 are data that I want to use as a unique ID in order to extract all other columns as a separate arrays with the same unique ID.
my example where unique id is in column 1:
subs = [1 1 5 6 ;2 1 4 5;3 1 4 5;1 1 2 5;2 1 5 8;4 1 4 8;2 1 7 8;4 1 5 4;2 1 2 2;1 2 5 5] % data
subs_unique=unique(subs(:,1)) % identifying the unique id in column 1 but it can also be column 14
A = accumarray(subs,subs_unique,[],@(x) {x}) % gives an error
desired result:
A{1}= [1 1 5 6;1 1 2 5;1 2 5 5]
A{2}=[2 1 4 5,2 1 5 8;2 1 7 8;2 1 2 2] and so on
Thansk a lot,
Cheers,
Mark

Accepted Answer

Daniel M
Daniel M on 30 Oct 2019
As Walter also suggested:
[~,~,locGroups] = unique(subs(:,1));
% also look at [~,~,locGroups] = unique(subs(:,1),'stable');
A = splitapply(@(v) {v}, subs, locGroups);
  1 Comment
sensation
sensation on 31 Oct 2019
Thanks a lot to both of you!
Cheers
M.

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More Answers (1)

Walter Roberson
Walter Roberson on 30 Oct 2019
Take the third output of unique() instead of the first. Or use findgroups()
splitapply() can also be used to do the splitting.

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