To Create a Variable with the name of a folder

Hello!

I have a variable called this way;

workfolder='C:\Users\Jorge\Desktop\Work_Christmas\Measurements\rpm_measurements\rpm0800\';

And i would like to create another variable and it is the end of the name of my directory (workfolder), in order to use it with a loop, in this case it would be:

new_variable = rpm0800

How could i do it?

Thanks!

[Jan]

Do you mean:

new_variable = 'rpm0800'

with the quotes?

[Peter]

Yes exactly!

Answer 1

[Stephen23]

While the question is rather unclear, it seems that the OP wishes to extract the last directory in the filepath string. This can be achieved using fileparts :

>> [A,B] = fileparts(workfolder(1:end-(workfolder(end)==filesep)))
A = 'C:\Users\Jorge\Desktop\Work_Christmas\Measurements\rpm_measurements'
B = 'rpm0800'

Note first this removes any trailing file separator character using the indexing of the workfolder string. An alternative is to use regexp to locate the last directory in the filepath string:

>> regexp(workfolder,'[^/\\]+(?=[/\\]?$)','once','match')
ans = 'rpm0800'

You should also have a good read of the MATLAB wiki, which covers all of these basic usage questions, with handy examples too:

http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F

[Peter]

Thank you very much Stephen, it worked

[Stephen23]

My pleasure!

Answer 2

[Image Analyst]

It's usually advised that you don't do that . However there is capability in MATLAB to do it and the FAQ shows some ways, such as using dynamic structure field names.

[Image Analyst]

Never mind. I thought you wanted to "create another variable and it is the end of the name of my directory" so I gave an answer for where the name of the variable was the folder, but evidently you wanted code where the contents (value) of the variable was the folder. It was not clear to me. Nonetheless, at least you know about our FAQ now.

[Peter]

Yes, thank you very much. I did not explain the question well at first, but thanks anyway!

[Image Analyst]

If, like I do, you have trouble figuring out complicated regexp expressions like '[^/\\]+(?=[/\\]?$)' , or would take too much time figuring that out, then you can use John D'Errico's incredibly handy and easy-to-use utility called allwords http://www.mathworks.com/matlabcentral/fileexchange/27184-allwords. It splits up the string into separate words and gives you control over the word separators. Here is some code that I think you'll find a lot easier to use and remember to use than those cryptic regexp expressions:

workfolder='C:\Users\Jorge\Desktop\Work_Christmas\Measurements\rpm_measurements\rpm0800\';

subFolders = allwords(workfolder, '\')
deepestFolder = subFolders{end}

I left off the semicolons at the end of the lines so you can see what it produces in the command window:

subFolders = 
    'C:'    'Users'    'Jorge'    'Desktop'    'Work_Christmas'    'Measurements'    'rpm_measurements'    'rpm0800'
deepestFolder =
rpm0800

What do you think, Peter? Is allwords() easier/simpler? Which do you prefer?

[Stephen23]

It is true that Regular Expressions have a rather cryptic syntax and can take a while to master, however they are a powerful tool that can be met in many different programming languages, and thus they are well worth the effort of learning. The fact that regexp is inbuilt means your code remains portable, without relying on any third-party functions (and licences...)

The example that Image Analyst gives above could also be achieved using standard MATLAB regexp:

>> regexp(workfolder,'\w+','match')
ans = {'C','Users','Jorge','Desktop','Work_Christmas','Measurements','rpm_measurements','rpm0800'}

Users wanting to practice and learn about Regular Expressions can try my compact Regular Expression Helper, which opens a figure and uses real-time updating of regexp's inputs and outputs to allow endless experimentation and refining of Regular Expressions:

http://www.mathworks.com/matlabcentral/fileexchange/48930-regular-expression-helper