How to replace specific characters in a cell array?
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I have a question about a code.
I have a cell array with strings and I would like to replace the last 5 characters with another for every cell array. I tried strrep but no use.
For example I have an array:
A={'MATHIEW','NIKOLIEW','SAMIEW','SAMOURAI'}.
I would like to replace ONLY in the strings that their last 3 characters have the elen\ments: IEW, with the elements 'YAU'.
I mean that I want my final array to be:
B={'MATHYAU','NIKOLYAU','SAMYAU','SAMOURAI'}.
Could you please help me?
2 Comments
the cyclist
on 2 Mar 2023
Can you give a small example of input and desired output, not just a description? When folks say "string", they often mean "character array", and it matters to the solution.
Accepted Answer
Image Analyst
on 4 Mar 2023
B={'MATHIEW','NIKOLIEW','SAMIEW','SAMOURAI'}
for k = 1 : numel(B)
if endsWith(B{k}, 'IEW', 'IgnoreCase', true)
B{k}(end-2 : end) = 'YAU';
end
end
B % Show in command window
More Answers (3)
the cyclist
on 4 Mar 2023
Edited: the cyclist
on 4 Mar 2023
With the additional description you added that clarified the problem, you can do this very easily with regexprep:
A = {'MATHIEW','NIKOLIEW','SAMIEW','SAMOURAI','IEWBLAHIEW'};
B = regexprep(A,'IEW$','YAU')
Note that this solution only replaces instances of IEW that occur at the end of the character array. (I added a case to illustrate that.)
0 Comments
the cyclist
on 2 Mar 2023
Edited: the cyclist
on 2 Mar 2023
Assuming you have character array elements, and not strings, here is one way:
% Inputs
CC_in = {'abcdeABCDE','xyzFGHIJ'};
replacementStr = '12345';
% Output
CC_out = cellfun(@(x) [x(1:end-5) replacementStr],CC_in,'UniformOutput',false)
This could be generalized, for example to automatically read the length of the replacement string:
% Inputs
CC_in = {'abcdeABCDE','xyzFGHIJ'};
replacementStr = '12';
% Output
L = numel(replacementStr);
CC_out = cellfun(@(x) [x(1:end-L) replacementStr],CC_in,'UniformOutput',false)
2 Comments
the cyclist
on 2 Mar 2023
Just going to tag on to this answer, that there are other methods for strings. It might be more common for strings to be stored in a string array than a cell array. (This is arguably a better approach, if you do not have mixed datatypes contents to store.)
% Inputs
CS = ["abcdeABCDE","xyzFGHIJ"];
replacementStr = "12345";
% Define the string lengths, for convenience
LCS = strlength(CS);
L = strlength(replacementStr);
% Output
CS_out = replaceBetween(CS,LCS-L,LCS,replacementStr)
Stephen23
on 2 Mar 2023
Edited: Stephen23
on 3 Mar 2023
"This is arguably a better approach"
Agreed. In fact the MATLAB documentation is even stronger even than that, it specifically recommends against storing string scalars in a cell array:
"When you have multiple strings, store them in a string array, not a cell array. ... String arrays are more efficient than cell arrays for storing and manipulating text. ... Avoid using cell arrays of strings. When you use cell arrays, you give up the performance advantages that come from using string arrays."
Venkatanarasimha Hegde
on 18 Mar 2023
Edited: Venkatanarasimha Hegde
on 18 Mar 2023
A = {'MATHIEW','NIKOLIEW','SAMIEW','SAMOURAI','IEWBLAHIEW'};
for i = 1:length(A)
temp = A{i};
if strcmp(temp(end-2:end),'IEW')
temp(end-2:end) = 'YAU';
end
A{i} = temp;
end
disp(A)
This is a much simpler version using loops. Even beginners can try to implement such codes who don't know much about regexp or complicated constructs.
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