Need to find files in a dir structure with similar but not identical names

I am trying to pull data from multiple files in a directory. I have written a for loop to get to the specified file, but when I search for the file using an * is cannot be found. For example, the file name 072814_Nominal.xls and another file in the same directory might be called 081213_Nominal.xls. I want to pull date from only files with "Nominal" in the name. I have tried using the below loop

D=dir(pathname);
for i=1:length(D)
    if D(i).name=='*Nominal.xls' %this line is trouble - says matrix dimensions must agree
        filename=fullfile(pathname,D(i).name);
        temp(i)=xlsread(filename,'Sheet1','R4');
    else
    end
end

but I am getting the "Error using ==", "matrix dimensions must agree" error and I cannot find a way to make Matlab find the file that looks like 'Nominal' or 'Nominal.xls' (I have tried both). Please help!

[per isakson]

• See regular expressions or

    D = dir( '*Nominal.xls' );

' Matlab don't support anything close to D(i).name=='*Nominal.xls'

Answer 1

[Ahmet Cecen]

Look for an implementation of grep or agrep for MATLAB. However if your problem has a monotonic redundancy, I might be able to suggest an alternative. For example, if you are only concerned about files ENDING with a very specific name (without possibility of spelling errors) such as '_nominal.xls', then here is a very lazy way to do it.

files = dir('*.xls');
for k = 1:length(files)
    current=files(k).name;
    check(k)=strcmp(current(end-10:end),'nominal.xls');
end
list=find(check);
images = cell(1, length(list));
for k = 1:length(list)
    data{k}=AN_APPROPRIATE_LOAD_FUNCTION_FOR_XLS_WITH_YOUR_PARAMETERS(files(list(k)).name);
end

Now only files whose name has the last 11 characters exactly 'nominal.xls' is loaded into the cell data.

Answer 2

[Image Analyst]

Don't use

D(i).name=='*Nominal.xls'

use strfind() instead

if ~isempty(strfind(D(i).name, 'Nominal.xls'))   % Don't use *Nominal use Nominal

[Alex]

This does not work, because the file is not just called 'Nominal.xls' it will have a timestamp in the name of the file. Therfore using strfind will always come up empty because the file name needs to match That is why I was using the * to try and be a placeholder for an arbitrary timestamp. Do you have any way to search for a string that will only be a partial of the full string of the filename?

[Michael Haderlein]

Have you tried? I guess you mix up strfind with strmatch.

[per isakson]

@Alex, try this

    filename = '081213_Nominal.xls';
    pos = strfind( filename, 'Nominal.xls' )
    isf = not( isempty( strfind( filename, 'Nominal.xls' ) ) )

it returns

    pos =
         8
    isf =
         1

[Image Analyst]

I agree with the others. strfind would have worked if you had just tried it, and as per just proved. The fact that a time stamp is somewhere in the filename does not matter at all - not sure why you thought it would unless you just didn't even read the documentation for the strfind function.

Answer 3

[per isakson]

An alternative

    D = dir( fullfile( pathname, '*Nominal.xls' ) );
    for jj = 1 : length(D)
        filespec = fullfile( pathname, D(jj).name );
        temp(jj) = xlsread( filespec, 'Sheet1','R4');
    end

Answer 4

[John]

Hi. I would like to add one piece of advice. In MATLAB, string comparisons for the purposes of logical testing are best done with 'strcmp'. You likely got that matrix dimensions error because strings in MATLAB are character arrays and if the filenames have different lengths then so will the character vectors that represent them. Strcmp, strfind, etc... are the way to go for string comparisons.