# find multiple words in a cell

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Vincent I on 9 Jan 2013
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

Ryan Livingston on 9 Jan 2013
A one-liner:
cellfun(@(x)sum(ismember(A,x)), B)
Vincent I on 9 Jan 2013
Fantastic, thank you . thats what I was looking for

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
Jan on 10 Jan 2013
Edited: Jan on 10 Jan 2013
The decision is easy:
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.

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?
Vincent I on 9 Jan 2013
Edited: Vincent I on 9 Jan 2013
Solved my problem by doing the folowing:
A=TF(:,1).';
A=regexprep(A, ' ','');
A=regexprep(A, '_(\w*)','');
B={'aa','bb2c','bb25c','xy3c','m56c','etc56c'};
C=cellfun(@(x)sum(strcmp(A, x)), B);
Thank you

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}));
...
Vincent I on 10 Jan 2013