problems using 'dir' and including search words

Having problems using the function 'dir' in the following setting:

The goal is to make a structure array, each element containing the information about the files fullfilling the name-requirements specified in the command (see *).

             dirData = dir([path,filename,'_Id = a*.log'])

()'path' is a well defined directory, 'filename' contains the first part of the name of each file(s) I need, '_Id=a.log' is the remaining part of the file(s) I need.

When attempting this in the command window, I simply obtain a structure array with zero elements, although I know that the directory implied by path contains 30 of these files.

Any help is much appreciated. Regards

[Yowh]

Can you give me 2 - 3 example names of your files ?

[Naum Derzhi]

You need filesep between path and filename, otherwise you are not searching inside path directory. As a matter of taste, rather than writing

dir([path,filesep,filename,'_Id = a*.log'] )
I would use fullfile, like this:

dir(fullfile(path,[filename,'_Id = a*.log']))

These two expressions are equivalent.

Answer 1

[Matt J]

Just a guess,

    dirData = dir([path,filesep, filename,'_Id = a*.log'])

Otherwise, print [path, filename,'_Id = a*.log'] to the command window and see what you're really feeding to DIR.

Answer 2

[Jan]

Do not shadow the very important function path() by a variable.

Matt J's suggestion to insert a file separator is a good idea, Sometimes folders are stored with a trailing separator (e.g. 'C:\'), sometimes without it. A flexible solution:

dirData = dir(fullfile(folder, [filename,'_Id = a*.log']));

Further idea: Do the filename contain spaces around the '='? In the text of the question you write: '_Id=a*.log' without spaces.

Does "struct array with zero elements" mean, that the array is empty, or that it contains zeros as elements?

Anyhow, if folder is really an existing path (please check this again), the dir command finds all matching file names. I promise that Matlab does not hide existing files magically, so there must be a bug elsewhere in the code.

Answer 3

[Kim]

Thanks for all your comments and answers. I managed to find the problem by verifying my 'path' variable - it was missing a '\' at the end, leading to a directory that didn't exist.. Cheers