How to Apply Cell-array to Matlab's exist() with directories?

I want to check if directories exist but work them in a cell-array. Matlab where the data is in the cell array in fullDirectories

home='/home/masi/';
directories={ 'Images/Raw/'; 'Images/Data/'; 'Images/Series/' };
fullDirectories = strcat(home, directories);

I can check one directory by exist('/home/masi/', 'dir');. Pseudocode

existCellArray(fullDirectories, 'dir-cell');

Matlab: 2016a
OS: Debian 8.5

Solution

Here's one approach.

%%% in file existCellArray.m
function Out = existCellArray (FullDirs)
% EXISTCELLARRAY - takes a cell array of *full* directory strings and tests if
%   they exist.

  MissingDirs = {};
  for i = 1 : length(FullDirs)
    if exist(FullDirs{i}, 'dir') 
      continue
    else 
      MissingDirs{end+1} = FullDirs{i}; 
    end
  end

  if isempty(MissingDirs); % Success
    Out = true; 
    return; 
  else % Failure: Missing folders detected. Print diagnostic message
    fprintf('Folder %s is missing\n', MissingDirs{:})
    Out = false;
  end
end

%%% in your console session:
Home = '/home/tasos/Desktop';
Dirs = {'dir1/subdir1', 'dir2/subdir2', 'dir3/subdir3'};
FullDirs = fullfile(Home, Dirs); % this becomes a cell array!
existCellArray (FullDirs)

%%% console output:
Folder /home/tasos/Desktop/dir2/subdir2 is missing
Folder /home/tasos/Desktop/dir3/subdir3 is missing
ans = 0

Note that one shouldn't automatically have a dislike for loops; I feel that in this case it is preferable:

it is efficient
it is clear, readable, debuggable code (whereas the output from cellfun is cryptic and hard to put to further use)
it allows for custom handling

a good for loop can actually be faster:

>> tic; for i = 1 : 1000; cellfun(@(x)exist(x, 'dir'), FullDirs); end; toc
Elapsed time is 3.66625 seconds.
>> tic; for i = 1 : 1000; existCellArray(FullDirs); end; toc;
Elapsed time is 0.405849 seconds.