Order CSV based on underlying timestamp OR using correct number

We extracted data using LabVIEW and got these kind of files:
For this measurement we have 151 files. But when I try to read them using this code:
%% declare folder containing the files
d = uigetdir(pwd, 'Select a folder');
csvFiles = dir(fullfile(d, '*.csv')); % get all csv files
% csvFilesOrdered = natsortfiles({csvFiles.name});
I tried ordering it through natsortfiles function but this does not work. What we get is:
Is there an easy way to solve this so it reads the files in the correct order? There should be a way to easily extract this but I cannot find it.
Thanks in advance!

1 Comment

"I tried ordering it through natsortfiles function but this does not work."
natsortfiles now directly sorts the output from DIR:
>> S = dir('*.txt');
>> S.name
ans =
'1.txt'
ans =
'10.txt'
ans =
'2.txt'
>> S = natsortfiles(S); % alphanumeric sort by filename
>> S.name
ans =
'1.txt'
ans =
'2.txt'
ans =
'10.txt'

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 Accepted Answer

Fixed it using:
[r inx]=sort({csvFiles.date});
csvFiles = csvFiles(inx);

3 Comments

You are sorting by the character vector if the date field, which includes text representation of the month and (for some locales) has the date units not in sequence from largest to smallest.
It is unlikely to sort robustly into the order that you want.
It gives me the csvFiles 1x151 struct in the correct order like this:
So I think that is enough? I now get the expected results on the graph.
EDIT: I think sorting the way you did would give the same result.
"I think sorting the way you did would give the same result."
Not at all.
The way I showed you in my comment sorts the filenames alphanumerically.
Your approach will sort August before February, and the 1st of any month in 2021 before the 2nd of any month in 2020. Have you considered what it really means to sort the character vectors of the date field?
If the dates were given in an ISO 8601 format then your approach would give a robust sort order (by file modification date), but they aren't, so in general the order is not meaningful. Using the datenum field would be robust.

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R2020b

Asked:

on 16 Feb 2021

Edited:

on 18 Apr 2021

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