regexp: either 'once' or 'all'
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Hi, I want to do a search only for the first n times. But it seems the 'options' in regexp can only do 'once' or 'all'. no intermediate choice, say '5', huh? thanks a lot!
답변 (2개)
Walter Roberson
2013년 11월 24일
(pattern){5}
In some cases what you might be after more might be
N = 5; %times to match
Rexpat = [ repmat( ['(' pattern '[).*?]', 1, N-1), ')' ];
regexp(string, Rexpat)
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Cedric
2013년 11월 25일
편집: Cedric
2013년 11월 25일
There should be a 3rd param. 'once' in the call to REGEXP, to avoid getting multiple matches if there are multiple times N occurrences of the initial pattern.
@Anthony: I would profile both the Rexmat pattern and the original pattern, because reducing the number of matches by increasing the complexity of the pattern doesn't always lead to an increase in performance. It's quite the opposite in fact.
Image Analyst
2013년 11월 25일
Perhaps you want strfind():
A='I have a dream have a dream have a dream bla bla bla...';
indexes = strfind(A, 'dream') % Find all locations.
indexes = indexes(1:5); % Take first 5 only.
In the command window:
indexes =
10 23 36
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Image Analyst
2013년 11월 25일
There's an old saying on how to write and speak: "Never say "Blah, blah, blah" when "Blah" will do. ;-)
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