Sort according to specific string contained in file name

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I have two lists of file names (including the whole path), at some point within the file name there is a subject ID and both lists contain exactly the same 25 IDs because there are two sets of files from each study participant. I need to sort the two lists so that the IDs correspond at each row, i.d. I want something like
List A List B
010822_AB030391 240922_AB030391
130922_FS120387 050322_FS120387
but right now what I have is
List A List B
010822_AB030391 050322_FS120387
130922_FS120387 240922_AB030391
because the lists are just sorted according to the first character and so the IDs don't correspond.
I had several ideas but they all seem too complicated or don't work well, e.g. I tried to split the file names at the underscore, to sort alphabetically and then merge the parts again. I also tried isolating the ID from one list, looping through that isolated list and finding the corresponding entry in the second list that contains a specific ID. But I think there should be a more elegant way to do this and I'd be happy to hear any tips! Right now both lists are character arrays, but maybe they should be a struct or something more easily manipulated.
TL on 24 Jun 2022
Yes exactly, however there are some more underscores in the path before the file name, e.g.
'D:\DATA\XY\Project_XY\\label_sPR12345_AB67890-0011.nii '
The number of characters before the ID is always the same, also the number of delimiters before it

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Accepted Answer

Karim on 24 Jun 2022
Edited: Karim on 24 Jun 2022
You can try spliting the lists, then ordering them and then using the indixes to sort the original list:
ListA = ["010822_AB030391";
ListB = ["050322_FS120387";
% temporarly split the string to use the ID
tmpListA = split(ListA,"_");
tmpListB = split(ListB,"_");
% sort list A
[ListA_sort, orderA] = sort(tmpListA(:,2));
% find the corresponding order for list B
[~,orderB] = ismember(ListA_sort,tmpListB(:,2));
% order the original list
ListA = ListA(orderA)
ListA = 2×1 string array
"010822_AB030391" "130922_FS120387"
ListB = ListB(orderB)
ListB = 2×1 string array
"240922_AB030391" "050322_FS120387"
TL on 24 Jun 2022
Works perfectly, thank you so much! This will be very useful long term, this issue keeps coming up in my project

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More Answers (1)

Stephen23 on 24 Jun 2022
S = ["D:\DATA\XY\Project_XY\label_sPR12345_AB67890-0011.nii";
[~,X] = sort(regexp(S,'[A-Z]+\d+\-','match','once'));
S = S(X)
S = 3×1 string array
"D:\DATA\XY\Project_XY\label_sPR40922_AB03091-0011.nii" "D:\DATA\XY\Project_XY\label_sPR12345_AB67890-0011.nii" "D:\DATA\XY\Project_XY\label_sPR30922_FS12038-0011.nii"


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