find a string in a character array

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A is an m x n character array (I think that is the right term. It says m x n char in the workspace under value).
I want to find a certain row depending on the characters. So say I have a string s of size 1 x n. I want something like this:
find(strcmp(s,A(1:m,:)))
I messed around with ismember instead of strcmp a little too. Can't get it right. I only want it to return an indicator if the row matches the string s.
help is appreciated. Thanks.

Accepted Answer

Matt Fig
Matt Fig on 13 Sep 2012
Edited: Matt Fig on 13 Sep 2012
A = ['asdf';'lelr';'wkre';'pope']
idx = all(ismember(A,'lelr'),2)
Now if you need linear indices rather than a logical index, use:
lidx = find(idx)
  1 Comment
Jonathan
Jonathan on 29 Jan 2019
This solution will match all strings that contain any of the characters in the string, not unique matches. See my answer below for an example and a soluton to fix this issue.

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More Answers (2)

Jonathan
Jonathan on 29 Jan 2019
The answer by Loginatorist was incorrect for my problem that is I believe the same as described by the OP. Below is an example of when the solution gives wrong results:
Occupations = ['educator ';'doctor '];
all(ismember(Occupations,'doctor '),2)
all(ismember(Occupations,'educator '),2)
Output:
ans =
5×1 logical array
0
1
ans =
5×1 logical array
1
1
Clearly, the second match is wrong, as doctor contains all the characters contained within educator.
A solution that fixes this is to use cellstr and strcomp:
OccupationsCell = cellstr(Occupations);
strcmp('doctor',OccupationsCell)
strcmp('educator',OccupationsCell)
Output:
ans =
2×1 logical array
0
1
ans =
2×1 logical array
1
0
  1 Comment
Stephen23
Stephen23 on 29 Jan 2019
Other options: use the 'rows' option:
>> Occupations = ['educator ';'doctor '];
>> ismember(Occupations,'doctor ','rows')
ans =
0
1
Use a cell array:
>> ismember(cellstr(Occupations),'doctor')
ans =
0
1

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Edward Umpfenbach
Edward Umpfenbach on 13 Sep 2012
Great. Thanks.
Was just missing the "all" part.

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