Help with regexp of varying filenames

I am sorting through files, trying to extract files using naming attributes.

The most common filename looks like this one with various letters/numbers after the second MESA:

'E:/MESA/IMAGES/Exam1/8015872/010612091858/images/MESA..._8015872_20010120_145658'

But there are some expections that I need to account for like (Notice the ...MAF and MESA...MAF):

'E:/MESA/IMAGES/Exam1/8015872/010612091858/images/...MAF_8015872_20010120_145658'
'E:/MESA/IMAGES/Exam1/8015872/010612091858/images/MESA...MAF_8015872_20010120_145658'

The first path works with the code below, but the second path causes problems.

startIndex = regexp(cur_study_path,'MESA');
studyName = cur_study_path( max(startIndex): end);

Is there anyway to default to:

startIndex = regexp(cur_study_path,'MAF')

when the first path isn't present, without including path names like the third path?

[Image Analyst]

I don't understand. What do you mean by "expectations"? You expect that some filenames will have MAF in them? OK, so what if they do? I'm not sure what you want to do in the cases

1. MAF is in the base filename
2. MAF is NOT in the base filename

Please clarify what you want to do in each case. What is the desired output in each case?

[Cris LaPierre]

And pleaes provide the full pathnames. It's hard to propose a solution for the exceptions when we don't know all the details.

[Image Analyst]

Do you perhaps want to do something like this

filename = strrep(filename, 'MAF', ''); % Remove MAF from filename.

or this;

for k = 1 : numberOfFiles
    thisFileName = whatever % Get filename somehow...
    if contains(thisFileName, 'MAF', 'IgnoreCase', true)
        continue; % Skip files with MAF in the name.
    end
    % Else process files with no MAF in the name.
end

Answer 1

[Cris LaPierre]

Perform 2 checks, one for MESA, one for MAF. They use max on the combined result.

% Case 1
cur_study_path='E:/MESA/IMAGES/Exam1/8015872/010612091858/images/MESA..._8015872_20010120_145658'

cur_study_path = 'E:/MESA/IMAGES/Exam1/8015872/010612091858/images/MESA..._8015872_20010120_145658'

siMESA = regexp(cur_study_path,'MESA');
siMAF = regexp(cur_study_path,'MAF');
studyName = cur_study_path( max([siMESA, siMAF]): end)

studyName = 'MESA..._8015872_20010120_145658'

% Case 2
cur_study_path='E:/MESA/IMAGES/Exam1/8015872/010612091858/images/...MAF_8015872_20010120_145658';

siMESA = regexp(cur_study_path,'MESA');
siMAF = regexp(cur_study_path,'MAF');
studyName = cur_study_path( max([siMESA, siMAF]): end)

studyName = 'MAF_8015872_20010120_145658'

% Case 3
cur_study_path='E:/MESA/IMAGES/Exam1/8015872/010612091858/images/MESA...MAF_8015872_20010120_145658';

siMESA = regexp(cur_study_path,'MESA');
siMAF = regexp(cur_study_path,'MAF');
studyName = cur_study_path( max([siMESA, siMAF]): end)

studyName = 'MAF_8015872_20010120_145658'