find multiple words in a cell
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Hi, is there a way to compare and return a number for the matching words in two unequal cells?
A={'a','a','a','b','b','d'} B={'a','b','c','d','e','f','g','h'}
return C=3,2,0,1,0,0,0,0
Thank you
Accepted Answer
More Answers (3)
Matt J
on 9 Jan 2013
If the "words" will really always be single letters, you could do it looplessly with
>> histc([A{:}], [B{:}])
ans =
3 2 0 1 0 0 0 0
6 Comments
Vincent I
on 9 Jan 2013
Matt J
on 9 Jan 2013
Post this as a new question. When you do, explain why 'b' gets only a count of 2 even though it occurs 3 times in A. Also explain what would happen if a letter occurs twice in the same string, e.g.
A={'a_1ab','bb'}; B={'a','b'};
Daniel Shub
on 9 Jan 2013
@Vincent So you are looking for non-exact matches? I don't see your accepted answer works for that.
And, although this is a new question, I feel that it is not far away for the initial question which I dont see why should require a new post
It doesn't require it, but if you post it as a new question, people have the opportunity to gain points from answering you (now that you've already accepted Ryan's answer), and so will be more incentivized to do so.
The decision is easy:
New question, new thread.
And:
Additional information to an existing question is added by editing the question and marking the changes by "[EDITED]". Then this is clarification and *not* a new question.
Hiding important information in deeply nested comments to already accepted questions is a bad idea.
Daniel Shub
on 9 Jan 2013
I am sure that this is over thinking the solution and I doubt that using regexp is optimal, but I was curious how bad it would be.
x = regexp(A, cell2mat(cellfun(@(x)['(?<', x, '>', x, ')|'], B, 'UniformOutput', false)), 'names');
cellfun(@(x)length([y.(x)]), fieldnames([x{:}]))'
I is there a better way to do this with regexp?
1 Comment
Jan
on 10 Jan 2013
[EDITED, Jan, moved from comments to the accepted question]
ISMEMBER sorts the inputs and performs a binary search. This can be much faster and much slower than an unsorted comparison by:
cellfun(@(x)sum(strcmp(A, x)), B)
I claim without a proof, that a loop is faster:
R = zeros(1, numel(B));
for iB = 1:numel(B)
R(iB) = sum(strcmp(A, B{iB}));
end
[EDITED 2] And if you want to compare the leading character(s) only:
...
R(iB) = sum(strncmp(A, B{iB}, length(B{iB}));
...
1 Comment
Vincent I
on 10 Jan 2013
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