Find number of files in multiple subfolders with specific extension

Hello,

I have multiple sub folders in one main folder. These multiple sub folders contains files with the same extension .pgm. How do I go about finding the total number of files in all the subfolders with that specific extension?

I am trying the following:

x = '*.pgm';
AA = size(dir(x),1)

How do I then go through each subfolders?

Answer 1

[Image Analyst]

dir() can now look inside subfolders if you use two asterisks . See the help.

[monkey_matlab]

I did a:

dir('**.pgm')

in the main folder, but I got the response '**.pgm' not found.

I also did a

help dir

but could not get a proper way to get the number of files in all the subfolders.

[Image Analyst]

You didn't use it correctly. Check the help again. See my attached demo for how to use it.