How to read files from sub folders in sorted order?

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Parthiban C on 10 Aug 2018
Commented: Stephen on 19 Jan 2022 at 8:16
Sub folder names are something like this. Time_0, Time_0.5, Time_1, Time_2, Time_10. The file name in all the sub folders are same. Matlab sort these folder names in the order Time_0, Time_0.5, Time_1, Time_10, Time_2. But I want the files to be loaded from smallest to largest time. Someone Please help me with this?
Stephen on 19 Jan 2022 at 8:10
"the answer by konard and stephen is good but if you sort by time does'nt give good results..."
My answer doesn't just sort by "Time", but sorts by the entire content of the foldernames, incuding the number values.

Edited: Konrad on 10 Aug 2018
Hi, one solution would be to convert the time suffix to numeric and sort the numbers:
d = dir('Time*');
n = {d.name};
t_char = regexp(n,'\-?[\d\.]+\$','match','once');
t_num = str2double(t_char);
[~,idx] = sort(t_num);
d_sort = d(idx);

Stephen on 10 Aug 2018
Edited: Stephen on 19 Jan 2022 at 8:09
The simplest solution is to download my FEX submission natsortfiles, which was written to solve exactly the problem that you are having:
There are plenty of examples in the Mfile help, the online documentation, and also in the HTML examples. Note that
• because the numbers include decimal values you will need to specify the regular expression.
• because you are sorting foldernames you will need to specify the 'noext' option.
D = 'path where subfolders are';
S = dir(fullfile(D,'Time_*'));
S = natsortfiles(S([S.isdir]),'\d+\.?\d*','noext')
Stephen on 19 Jan 2022 at 8:16
Example using a cell array:
C = {'Time_0', 'Time_1.5', 'Time_9.5', 'Time_1', 'Time_10', 'Time_2.5'};
D = natsortfiles(C,'\d+\.?\d*','noext')
D = 1×6 cell array
{'Time_0'} {'Time_1'} {'Time_1.5'} {'Time_2.5'} {'Time_9.5'} {'Time_10'}