How to extract only one file from a zipped folder

I have a zipped folder with multiple subfolders in it. The subfolders aren't zipped but I want to extract two files from a subfolder of a subfolder. I have about 1000 subjects that I want to do this for so I have to make a for loop and cannot do it by individual commands.

path_r = 'H:/emotion/data/';

cd(path_r)

subj_list = dir('*');

subj_list(1:2) = [];

for subji = 1%:length(subj_list)

path = [path_r subj_list(subji).name '/MNINonLinear/Results/tfMRI_EMOTION_RL/'];

^ this is the code for to the folder with the file

unzip([path 'tfMRI_EMOTION_RL.nii.gz'], ['H:/emotion/' subj_list(subji).name '_RL'])

unzip([path 'Motion_Regressors'], ['H:/emotion/' subj_list(subji).name '_RL'])

^These are the two files I want to extract to a new folder

end

The subject list is the name of the subject ex. 123456. However, the only way to get this list is if I extract the files. The true name of the file is "123456_3T_rfMRI_REST1_preproc" so I would need to find a way to make a subject list with only the numerical subject name because it is required for the path. Please let me know what I can do to change my code and make sure it works.

Answer 1

[chrisw23]

NET.addAssembly("System.IO.Compression.FileSystem");                                                                                             
NET.addAssembly("System.IO.Compression");                                                                                                        
                                                                                                                                                 
function [unzippedFileNames,msg] = unzipFromArchive(obj,zipArchivePath,searchString,ignoreCase,unzipPath)                                        
% unzip specific files from given archive                                                                                                        
% search string can bei a complete file name or a related part of the file name                                                                  
% '*' wildcards are not supported                                                                                                                
                                                                                                                                                 
import System.IO.*                                                                                                                               
import System.IO.Compression.*                                                                                                                   
import System.IO.Compression.ZipFileExtensions.*                                                                                                 
                                                                                                                                                 
msg = obj.DefaultNoError;                                                                                                                        
archStream = File.Open(zipArchivePath, FileMode.Open);                                                                                           
try                                                                                                                                              
    arch = ZipArchive (archStream, System.IO.Compression.ZipArchiveMode.Read);                                                                   
    zipFileList = NET.createGeneric('System.Collections.Generic.List',{'System.String'},arch.Entries.Count);                                     
    enArch = arch.Entries.GetEnumerator;                                                                                                         
    overwrite  = true;                                                                                                                           
                                                                                                                                                 
    while enArch.MoveNext                                                                                                                        
        zipFileList.Add(enArch.Current.Name);                                                                                                    
    end                                                                                                                                          
                                                                                                                                                 
    zipFiles = string(zipFileList.ToArray)';                                                                                                     
    searchIndex = find(zipFiles.contains(searchString,'IgnoreCase',ignoreCase)); % zero based .net index                                         
    unzippedFileNames = zipFiles(searchIndex);  % search result                                                                                  
                                                                                                                                                 
    if ~isempty(searchIndex)                                                                                                                     
        for sglFileIndex = searchIndex'                                                                                                          
            ZipFileExtensions.ExtractToFile (arch.Entries.Item(sglFileIndex-1),Path.Combine(unzipPath,zipFiles(sglFileIndex)), overwrite)        
        end                                                                                                                                      
    else                                                                                                                                         
        msg = "archive file names without match to search string '" + searchString + "'";                                                        
    end                                                                                                                                          
catch ex                                                                                                                                         
    msg = ex.message;                                                                                                                            
    unzippedFileNames = [];                                                                                                                      
end                                                                                                                                              
                                                                                                                                                 
% release archive file                                                                                                                           
arch.Dispose();                                                                                                                                  
archStream.Close();                                                                                                                              
                                                                                                                                                 
end                                                                                                                                              

modify this as needed (copied out of one of my classes)

Answer 2

[Luca Ferro]

This cannot be done using matlab only, it requires Java as well.

You can refer to this thread for extracting file names and paths from a zipped archive

And to this thread here for unzipping single files.