Reading CSV files in a sequence based on numeric value in file name

Question

Sunny 2019-2-16

0
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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/445314-reading-csv-files-in-a-sequence-based-on-numeric-value-in-file-name

回答： Are Mjaavatten 2019-2-19

Hello,

I am trying to read files in a sequence based on a numeric value in file name. The file names are shown a below. The numeric value at the end of each file is in a sequence. I am trying below code but this doesn't work. I am sure that I am doing something wrong with the * symbol placement.

Walk_ACLR_055_041_PSI_15_15_data_44.csv, Walk_ACLR_247_135_PSI_15_15_data_3.csv, Walk_ACLR_271_155_PSI_15_15_data_17.csv ......
    
clc;clear;
Labels = [];
for k = 1:150
    if exist (['*',num2str(k),'.csv'],'file')
        filename = ['*',num2str(k),'.csv']
        T = readtable(filename);
        H = height(T);
        Total = H/15;
        Labels = [Labels;Total];
    end
end

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Answer 1

Are Mjaavatten 2019-2-19

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/445314-reading-csv-files-in-a-sequence-based-on-numeric-value-in-file-name#answer_361708

在 MATLAB Online 中打开

d = dir('*.csv');
filenames = {};
index = 0;
k = 0;
for i = 1:length(d)
  % Using regexp with lookaround on the file name to find 
  % a sequence of digits preceeded by '_' and followed by '.': 
  no = regexp(d(i).name,'(?<=_)\d*(?=\.)','match');
  if ~isempty(no)
    k = k+1;
    filenames{k} = d(i).name;
    index(k) = str2num(no{end});
  end
end
% filenames contains all filenames of the correct form
% index contains the numeric value
% Now sort:
[~,ix] = sort(index);
filenames = filenames(ix);
% You can now process files in the correct order:
for i = 1:length(index)
  disp(filenames{i});  % or whatever...
end