MATLAB: Regexp to filter file names

dirregexp

Hello,
I would like to use a regexp to filter file names contained in a folder. I almost got it, but I have trouble handling cell that output the dir() function…
Let's imagine I have these files in the data folder :
DY463269-F 01-01-2017.xlsx
DY463269-F 01-01-2017.xlsx
DY463271-8 01-01-2017.xlsx
DY466290-M 01-01-2017.xlsx
My code is :
filesList = dir('data/');
serialList = regexpi({filesList.name}, '[a-z]{2}[0-9]{6}[a-z\-]{0,2}', 'match')
dateList = regexpi({filesList.name}, '[0-9]{2}-[0-9]{2}-[0-9]{2}', 'match')
data = cell2struct([serialList; dateList],{'Name','Date'},1)
data(3).Name
First, I guess we can do only one regexpi to get both information… But mostly, data(3).Name return me a cell and I would like it to simply be a string.
Any idea to fix this?
Thanks,
Max

Best Answer

filenames = {'DY463269-F 01-01-2017.xlsx'
         'DY463269-F 01-01-2017.xlsx'
         'DY463271-8 01-01-2017.xlsx'
         'DY466290-M 01-01-2017.xlsx'};
fileinfo_cell = regexpi( filenames, '^(?<serial>[a-z]{2}\d{6}[a-z\-]{0,2})\s+(?<date>\d\d-\d\d-\d\d)', 'names','lineanchors');
fileinfo = vertcat(fileinfo_cell{:});
fileinfo will then be a struct array with fields "serial" and "date".
With that particular set of data, the struct will have 3 elements, because DY463271-8 01-01-2017.xlsx does not match the pattern (the serial ends in -8 but the pattern does not permit numbers at that point.)
A generalization of the pattern would be
fileinfo = regexpi( filenames, '^(?<serial>\w\w\d{6}[\w-]{0,2})\s+(?<date>\d\d-\d\d-\d\d)', 'names','lineanchors')
Each \w corresponds to [a-z0-9_] -- the "word-building" characters. What you have now is more focused and you might need that focus, but sometimes it is useful to be more lenient.
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