I need to efficiently skip lines in text file

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Art Hartzell
Art Hartzell 2015-8-7
编辑： Cedric 2015-8-7
I'm reading in a formatted text data file and pulling data from it. Every so often there is a break in the data and its 4 lines long. I'm reading the lines with "fgetl" and right now to skip those lines I just use
for i = 1:4
line = fgetl(fileID);
end
This seems terribly inefficient and brute force. Is there a better way?
--Clarification The skipped lines have information in them, just information I don't use. I'm also trying to avoid saving any information temporarily for the skipped lines.
  1 个评论
Cedric
Cedric 2015-8-7
编辑：Cedric 2015-8-7
Could you give an example of both types of lines and define the elimination criterion?

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采纳的回答

Walter Roberson
Walter Roberson 2015-8-7
Repeated fgetl() is going to be more efficient than what the others have shown here when you are working with text files. fgetl() is a low-level routine that talks directly to the I/O stream used by the operating system libraries.
If you were working with non-text files (that is you did not use the 't' flag when you opened them) and if you knew exactly how many bytes the 4 lines occupied in total including the line delimiters, then you could fseek() forward that many bytes.

更多回答（1 个）

Azzi Abdelmalek
Azzi Abdelmalek 2015-8-7
编辑：Azzi Abdelmalek 2015-8-7
You can use textscan
fid=fopen('fic.txt');
str=textscan(fid,'%s','HeaderLines',5,'delimiter','\r\n');
fclose(fid)

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