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find function using wildcards

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sermet OGUTCU
sermet OGUTCU on 17 Sep 2021
Commented: Rik on 17 Sep 2021
fileID = fopen(full_file_name);
header = textscan(fileID, '%[^,\n]');
fclose(fileID);
end_of_header_line=find(contains(header{1,1},'* '));
Here, I find all line numbers of header includes any * with two spaces or more. I need to modify the last part of the above codes to find all line numbers includes * with two spaces and following four digit numbers such as;
* 2021
For example header includes:
/* GeoForschungsZentrum Potsdam
/*
/*
* 2021 3 28 0 0 0.00000000
The line numbers (end_of_header_line) produced from above codes includes all 4 lines. What I need to find only the last line.

Accepted Answer

Rik
Rik on 17 Sep 2021
You can use the patterns introduced in R2020b:
str={'/* GeoForschungsZentrum Potsdam '
'/* '
'/* '
'* 2021 3 28 0 0 0.00000000 '};
pat="*"+whitespacePattern(2,inf)+digitsPattern(1);
contains(str,pat)
ans = 4×1 logical array
0 0 0 1
Alternatively you can use regular expressions, which are not much harder to use.
  2 Comments
Rik
Rik on 17 Sep 2021
When you posted your question you had the opportunity to enter your release. Please do so next time. As you can see it is sometimes relevant.
str={'/* GeoForschungsZentrum Potsdam '
'/* '
'/* '
'* 2021 3 28 0 0 0.00000000 '};
pat=['\*',... % a literal *
'\s\s','\s*',...% two whitespace characters, followed by 0 or more
'\d']; % any digit
pos=regexp(str,pat) %regexp returns the position of a match
pos = 4×1 cell array
{0×0 double} {0×0 double} {0×0 double} {[ 1]}
%The legacy syntax of cellfun is the only case where it is faster than a
%loop. However, it doesn't work properly with all data types.
logical(cellfun('prodofsize',pos))
ans = 4×1 logical array
0 0 0 1

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