How to delete repeating header lines from text file
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Bruno Rodriguez
on 15 Sep 2016
Commented: Star Strider
on 16 Sep 2016
I have a text file consisting of a recurring sequence, made up of 4 header lines followed by 37 lines of data, then another 4 header lines, and so on (see attached txt file). One complication is that each set of headers is slightly different since it incorporates varying numbers. I want to delete all of these header lines and be left with the remaining data.
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Accepted Answer
Star Strider
on 15 Sep 2016
There is no end-of-file in the file you posted. Normally, I would use this code:
fidi = fopen('Bruno Rodriguez a160628.dat','r');
k1 = 1;
while ~feof(fidi)
data(k1) = textscan(fidi, repmat('%f',1,20), 'HeaderLines',4, 'CollectOutput',1, 'EndOfLine','\r\n');
fseek(fidi,0,0);
k1 = k1 + 1;
end
With the file you posted, it is necessary to detect the last record differently. I used fgetl and strfind, copying part of the last header manually to the strfind call.
This works:
fidi = fopen('Bruno Rodriguez a160628.dat','r');
lastrecord = 0; % Initialise ‘lastrecord’
k1 = 1; % Initialise Counter
while ~feof(fidi)
data(k1) = textscan(fidi, repmat('%f',1,20), 'HeaderLines',4, 'CollectOutput',1, 'EndOfLine','\r\n');
if lastrecord % If Previous Was ‘lastrecord’, Stop
break
end
fseek(fidi,0,0); % Restart At New Position
firstline = fgetl(fidi); % Read First Line
lastrecord = strfind(firstline, 'SJSU_Sodar_DiabloCanyon 06/28/2016 23:50:00'); % Find Last Record Section
fseek(fidi, -1, 0); % Back Up One Line So ‘textscan’ Will Read It
k1 = k1 + 1; % Increment Counter
end
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More Answers (1)
Walter Roberson
on 15 Sep 2016
Is the "SJSU" always going to be the same? If so then you could perhaps take advantage of the CommentStyle of textscan()
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