MATLAB: Export matched lines from two text files

exporttext file

I need to identify the same lines between the two text files, mwithrm21.txt and virgomrmdist.txt, based on column 7 of each files. These matches should then be exported into a new text file, while removing the matched lines from mwithrm21.txt.
I have attached the text files.
I drafted the code below:
content1 = fileread( 'mwithrm21.txt' ) ;
 content2_rows = strsplit( fileread( 'virgomrmdist.txt' ), sprintf( '\n' )) ;
 found = cellfun( @(s)~isempty(strfind(content1, s)), content2_rows ) ;
 output_rows = content2_rows(found) ;
 fId = fopen( 'similarvclf.txt', 'w' ) ;
 fprintf( fId, '%s\n', output_rows{:} ) ;
 fclose( fId ) ;
 output_rows = content2_rows(~found) ;
 fId = fopen( 'mwithrm21_new.txt', 'w' ) ;  % Remove the '_new' for overwriting original. 
 fprintf( fId, '%s\n', output_rows{:} ) ;
 fclose( fId ) ;
But, I do not know how to make it specific to only searching column 7 and then exporting the entire matched line to a new text file.

Best Answer

Here is a first draft. Test it and let me know if anything is unclear or doesn't work.
 % - Read files content as strings.
 content1 = fileread( 'mwithrm21.txt' ) ;
 content2 = fileread( 'virgomrmdist.txt' ) ;
 % - Extract last column of each content.
 codes1 = regexp( content1, '[^|]+(?=(\s|$))', 'match' ) ;
 codes2 = regexp( content2, '[^|]+(?=(\s|$))', 'match' ) ;
 % - Matches codes.
 [isMatch_1in2, match_posIn2] = ismember( codes1, codes2 ) ;
 % - Split content. Careful, whatever generates these files still uses
 %  carriage returns (\r) only.
 rows1 = strsplit( content1, char(13) ) ;
 rows2 = strsplit( content2, char(13) ) ;
 % - Output matches (version mwithrm21.txt). Use new line chars (\n) as 
 %  joint instead of carriage returns, change if you prefer \r.
 fId = fopen( 'matches.txt', 'w' ) ;
 fwrite( fId, strjoin( rows1(isMatch_1in2), '\n' )) ;
 fclose( fId ) ;
 % - Output non-matching rows of file 1.
 fId = fopen( 'mwithrm21_reduced.txt', 'w' ) ;
 fwrite( fId, strjoin( rows1(~isMatch_1in2), '\n' )) ;
 fclose( fId ) ;
 % - Output non-matching rows of file 2. Eliminate matching rows first.
 rows2(nonzeros( match_posIn2 )) = [] ;
 fId = fopen( 'virgomrmdist_reduced.txt', 'w' ) ;
 fwrite( fId, strjoin( rows2, '\n' )) ;
 fclose( fId ) ;
EDITs :
  • Replaced match_posIn2(match_posIn2~=0) with nonzeros( match_posIn2 ) after reading an answer by Matt J in another thread that mentions NONZEROS.
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