how to search and delete the nth ocurance of a text in a text file

Hallo,

I have a text file 'test.txt' . The contents of test file is as follows.

Tim is Home

John is happy

Sara is funny

Kevin is at work

John is happy

Cat and Dog

I want to open the test.txt file and delete the 'nth' occurance of 'John is happy '. I have attached the text file too. Thanks in advance.

eg. I want to delete the line with ' n th 'occurance.

so It can be 1st occurance

or 2nd Occurance.. etc

Regards,

Jaffrey

Answer 1

[madhan ravi]

s = fileread('test.txt');
v = regexp(s,'\n','split');
z = regexprep(s,'John is happy','',2) % 2 denotes the nth occurence
dlmwrite('sample.txt',z,'delimiter','')

[Adam Danz]

@ Jaffrey, note that this solution leaves an empty line in place of any row of text removed - that might be exactly what you're looking for but I just wanted to point that out.

[madhan ravi]

Adam Danz , he knows it ;)

[Adam Danz]

Is that hunch from your crystal ball? :D

[madhan ravi]

Exactly XD

Answer 2

[Adam Danz]

The question is unclear whether the goal is to remove the 2nd line of text or to remove the line(s) with "John is happy". The block below shows both interpretations.

% Import text
opts = delimitedTextImportOptions("NumVariables", 1);
opts.VariableNames = "txt";
test = readtable("C:\Users\adanz\Documents\MATLAB\savehere\matlabCentralDocs_trash\test.txt", opts);
test = table2array(test);

% Delete 2nd line
test(2) = []; 

% - OR - 

% Delete lines that match "John is happy"
idx = strcmpi(test, 'John is happy'); 
test(idx) = [];

% - OR - 

% delete nth occurance of "John is happy"
n = 2; 
idx = strcmpi(test, 'John is happy'); 
test(max(find(idx,n))) = []; 

% Write to txt file
fid = fopen('test2.txt','wt');
fprintf(fid,'%s\n',test{:});
fclose(fid);

[Jaffrey Hudson Immanuel Jeyakumar]

Thank you for the reply.

My question is to remove the line with 'nth' occurance of 'John is happy'.

eg. I want to delete the line with ' n th 'occurance.

so It can be 1st occurance

or 2nd Occurance.. etc

[Adam Danz]

OK, see updated answer.

[Jaffrey Hudson Immanuel Jeyakumar]

Thank you ! for the update .

Answer 3

[Jaffrey Hudson Immanuel Jeyakumar]

Thank you. It is working now.