# find a string in a character array

334 views (last 30 days)
Edward Umpfenbach on 13 Sep 2012
Commented: Stephen23 on 29 Jan 2019
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.

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)
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.

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
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

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

### Categories

Find more on Resizing and Reshaping Matrices in Help Center and File Exchange

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!