Can Matlab read the most recent made file in the default folder?

Hello, just want to know if Matlab can import the file that is most recent made based on their modified date and time?

I have several Excel files and want it read and do analysis?

Thanks.

Answer 1

[Jan]

A summary of the comments:

d            = dir('somefolder/*txt');
[~, index]   = max([d.datenum]);
youngestFile = fullfile(d(index).folder, d(index).name);  % [EDITED], typo fixed
                                                          % Thanks, Andres Morales

[Andres Morales]

Seems like you have an extra ")" on the 3rd line.

[Jan]

@Andres Morales: Thanks. I've fixed it.

Answer 2

[pfb]

Hi,

you could get the excel files with

 d= dir('*xls');

and then compare the dates. These are in

 d(j).date

You probably better convert them to numbers to compare them

 dd = zeros(length(d));
 for j = 1:length(d)
  dd(j) =datenum(d(j).date);
 end

 [tmp i]=max(dd);

 load(dd(i).name)

[C Zeng]

Thanks, pfb! Yes, get the date and transfer it into number.

What is there are many files generated in same and most recent day, can I compare the time? like d(j).time?

[pfb]

datenum should take care of that.

If a file is more recent than another one, its datenum would be a larger number. Take a look at the documentation of datenum.

[C Zeng]

Thanks, yes I just read it.

[Yan Kai Lai]

I used the answer by pfb to read the most recent txt file. To make the answer more complete:

d = dir('somefolder/*txt');
dd = zeros(length(d), 1); % to init as vector instead of square matrix
for j = 1:length(d)
    dd(j) = datenum(d(j).date);
end
[~, i] = max(dd); % tmp is the datenum, which is not necessary
lines = readlines(fullfile(d(i).folder, d(i).name)) % should be d instead of dd.

[Stephen23]

Converting to DATENUM is not required because the DIR output structure already contains serial date numbers, so that superfluous loop can be simply replaced by this:

dd = [d.datenum];

See: https://www.mathworks.com/help/matlab/ref/dir.html#bsnswnx-1-listing

https://www.mathworks.com/matlabcentral/answers/1656435-tutorial-comma-separated-lists-and-how-to-use-them

Answer 3

[Walter Roberson]

https://www.mathworks.com/matlabcentral/answers/99277-how-do-i-programmatically-detect-a-change-in-a-directory discusses several methods