Doug's MATLAB Video Tutorials

June 3rd, 2010

By Doug Hull

Doug first used MATLAB in 1994, could not figure it out until he got some help in 1995. He is now dedicated to making sure that no one else wastes a year of their life not knowing MATLAB like he did.

20:29 UTC | Posted in Format: Video, Level: Basic | Permalink | 7 Comments »

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7 Responses to “Find newest file in a directory”

1. Kevin Sheppard replied on June 3rd, 2010 at 20:59 UTC :
   

   !dir /od *.m
   

   at least on Windows

2. dhull replied on June 7th, 2010 at 17:36 UTC :
   

   @Kevin,

   Thank you, as with many of my videos the intent is more to take a simple example to show general techniques. This command does solve this specific problem very nicely though.

   Thanks,
   Doug

3. Vishu replied on June 28th, 2011 at 11:28 UTC :
   

   Excellent. This was of a great help to me because i have to read files with stamp. However, one small correction. In line 5, replace the ‘~’ with some variable eg. a. What kevin wrote was right though i cudn get how to obtain the latest file name.

4. dhull replied on June 29th, 2011 at 18:28 UTC :
   

   @Vishu,

   In newer versions of MATLAB, the ~ means “ignore this outout/input”.

   Doug

5. Dominik replied on May 24th, 2012 at 16:42 UTC :
   

   Hi, Neat trick getting the max of datenum. I would like to find the newest folder in my current directory so that I can rename it.
   I have a folder full of .zip files, I want to one at a time, rename the directory that it creates and then move on to the next .zip.
   If you do after unzip it includes . and .. as directories that are newer than anything else. Since I don’t have an extension to separate with, how can I differentiate between ., .., and actual folders? Thanks

6. Dominik replied on May 24th, 2012 at 17:19 UTC :
   

   Sorry, that didn’t come out as I wanted above:
   Neat trick getting the max of datenum. I would like to find the newest folder in my current directory so that I can rename it.
   I have a folder full of .zip files, I want to unzip one at a time, rename the directory that it creates and then move on to the next .zip.
   If you do dir after unzip it includes . and .. (and sometimes .DS_Store which I think gets created after unzipping) as files/directories that are newer than anything else. Since I don’t have an extension to separate with, how can I differentiate between ., ..,.DS_Store and actual folders? Some code I have that is a bit of a hack and the last line doesn’t work because you can dynamically reference(?) inside the unix command:

   files=dir;
   for i=3:length(files)
   unzip(files(i).name);
   fd=dir;
   for j=1:length(fd)
   dn=[fd(4:end).datenum];
   [~,newestI]=max(dn);
   [~,nom,~]=fileparts(files(i).name);
   old=fd(newestI+3).name;
   unix(‘mv old nom’)
   end
   end

7. Dominik replied on May 24th, 2012 at 17:44 UTC :
   

   I figured out my problem doing:
   files=dir(‘*.zip’);
   for i=3:length(files)
   [~,nom,~]=fileparts(files(i).name);
   unzip(files(i).name,nom);
   fd=dir(nom);
   cd(nom)
   cd(fd(end).name)
   unix(‘mv * ../’)
   cd ../
   rmdir(fd(end).name)
   cd ../
   end

   but I would still be curious if there is a way to not capture the . and .. in the dir command. Or more broadly, dir everything except . which could also be applied to everything but .jpg etc. Thanks!

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<pre class="code">
a = magic(3);
sum(a)
</pre>

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