selecting file from a database (.txt files) ?

Good Morning, I have a series of data, say in a folder, which are saved with this name: "NAME_NUMBEROFMACHINE_YYMMDD_HHmmSS" (YY= years, HH= hours, etc.) and I'd like to import to my workspace only the data of a specific day, or of a specific machine. Is there a way to do it easily in Matlab or should I use another programme? Thanks Gabriele

Answer 1

[Elias Gule]

    function files = listFiles(key,directory,ext)
    %%LIST FILES
    % key : the machine name or day
    %     : if searching for day , use a numeric value
    %     : and use a string when searching for machine name.
    % directory : the full path of the search folder.
    % ext : the desired file extension.

    % The name search is case-insensitive : regexpi was used instead of regexp
    %

    % NB: The code can surely be improved: This was just a quick solution.
        switch nargin
            case 1
                directory = '';
                ext       = '*';
            case 2
                ext       = '*';
            otherwise
                % DO NOTHING
        end

        if(isnumeric(key))
            isDaySearch = true;
        else
            isDaySearch = false;
        end

        if(isDaySearch)
            pattern = sprintf('.*%s_%s%02d_%s','\w+\d+','\d{4}',key,'\d{6}');
        else
            pattern = sprintf('.*%s%s',key,'\w+');
        end

        [status files] = fileattrib(fullfile(directory,ext));

        if ~isempty(files)
            files = {files(1:end).Name};
            files = cellfun(@(x) char(regexpi(x,pattern,'match')),files,...
                'UniformOutput',false);
            files = files(~cellfun('isempty',files));
        else
            files = cell(1,1);
        end
    end

[Elias Gule]

This function will output a cell array of files matching the key. You can then use the function "importdata" to load data from each file; if the files contain only numeric data then you can use the "dlmread" function which will save each file data in one matrix.

Answer 2

[Elias Gule]

Please see attached file.