This is probably a very simple question, but I am not able to find a straightforward solution.
[pathstr,name,ext] = fileparts('/xaaa/Data/Q2/CONUS/2002/PRECIPRATE.20020401.000000.tif')
Obviously, fileparts gives /xaaa/Data/Q2/CONUS/2002/
But I only want to access /xaaa/Data/Q2/CONUS/ and disregard the last section.
One way to do it is simply count the letters parthstr(1:20). But there must be an elegant alternative.
The most robust way to get a parent folder is to use '..' to access the folder above a provided folder. This is because it is independent of whether you specify an absolute or relative path as the input.
parent = fullfile(folder, '..');
In your case, since you have a filename and you want to get the parent, you can add a 'fileparts' call to that to get the direct parent folder, then pass it to the above.
parent = fullfile(fileparts(filename), '..');
This is more robust because it allows you to specify a relative file path such as 2002/PRECIPRATE.20020401.000000.tif which could fail if you tried to call fileparts multiple times.
If you only have a filename (with no directories because you're in the folder where the file is), you can use which to get an absolute path to the file.
parent = fullfile(fileparts(which(filename)), '..');
One simple way is to repeat the use of fileparts():
>> [pathstr,name,ext] = fileparts('/xaaa/Data/Q2/CONUS/2002/PRECIPRATE.20020401.000000.tif');
>> [parent_pathstr, name, ~] = fileparts(pathstr)
parent_pathstr =
/xaaa/Data/Q2/CONUS
name =
2002
Note: using the tilde ~ just ignores the file extension for the second call to fileparts() because you don't expect an extension.
There are three answers proposed already, but I do believe there's a better solution. I would match .*(?=/.*/) pattern using regexp, like this:
>> originalPath = '/xaaa/Data/Q2/CONUS/2002/PRECIPRATE.20020401.000000.tif';
>> res = char(regexp(originalPath, '.*(?=/.*/)', 'match'))
res =
/xaaa/Data/Q2/CONUS
If you need to go n levels deeper, just keep adding .*/ for each level, e.g.
>> res = char(regexp(originalPath, '.*(?=/.*/.*/)', 'match'))
res =
/xaaa/Data/Q2
For the OS-agnistic version, or if your path contains some mixture of back-slashes and forward-slashes, you can use the following regex: '.*(?=[/\\].*[/\\])'. Once again, to go several levels deper, just add an extra .*[/\\] for each level.
The benefit over using strsplit and fileparts is that you don't need to iterate anything - you get the answer with one simple regex.
Regarding .. - I myself used this solution for a long time for generating Matlab Path dynamically. However Matlab is sometimes not able to handle breakpoints correctly in the files that have .. in their path. To be exact, if you place a breakpoint in such a file, Matlab would ignore it unless there's another breakpoint that is triggered first (which is not in a file with .. in path).
It obviously handles relative paths as well.
Related
Basically, I build a list of files using ls, then want to loop through that list, read in a file, and do some stuff. But when I try to read the file in it fails.
Here is an example
r=ls(['Event_2006_334_21_20_11' '/*.r'])
Event_2006_334_21_20_11/IU.OTAV_1.0.i.r
which is a 1x80 char
fopen(r(1,:))
-1
but
fopen('Event_2006_334_21_20_11/IU.OTAV_1.0.i.r')
12 (or whatever its on)
works. I've tried string(r) and char(r) and sprintf('%s',r). If I just build the string like r = ['Event_2006_334_21_20_11' '/IU.OTAV_1.0.i.r'] it works. So it seems something about combining the different variable types that messes it up but I can't seem to find a workaround. Probably something obvious I'm missing.
Any suggestions?
ls returns a matrix of characters, which means each row contains the same number of characters. To indicate the problem, try:
['-' r(1,:) '-']
You will probably notice some whitespaces in front of the -. Unless you want to print the output to the command line, ls is not really useful. As mentioned by Alex, use dir instead.
A further tip regarding your last comment, concatenate file path using fullfile. It makes sure you get one file separator whenever concatenating:
>> fullfile('myfolder','mysubfolder','myfile.m')
ans = myfolder/mysubfolder/myfile.m
>> fullfile('myfolder/','mysubfolder','myfile.m')
ans = myfolder/mysubfolder/myfile.m
>> fullfile('myfolder/','/mysubfolder','myfile.m')
ans = myfolder/mysubfolder/myfile.m
In the below code I am trying to sort files based on a string within the name. I've been piecing this together with google searches and community help (I'm very new at matlab). Right now I'm getting two odd errors. First, when I try and make a folder, it creates some file (highlighted filein picture that I can't open and the wav files that should have been moved to the folder disappear.
I'm also having an issue where the code renames the first two data files moved to "01" and "01 (1)" and I have no idea why.
DirIn = 'C:\Folder\Experiment' %set incoming directory
eval(['filelist=dir(''' DirIn '/*.wav'')']) %get file list
for i = 1:length(filelist);
Filename = filelist(i).name
name = strsplit(Filename, '_');
newStr = extractBetween(name,7,8);
if strcmp(newStr,'01')
DirOut = fullfile(DirIn, '01');
mkdir DirIn DirOut
movefile(fullfile(filelist(i).folder, filelist(i).name), DirOut);
end
end
This should work:
DirIn = 'C:\Folder\Experiment'; %set incoming directory
filelist=dir(fullfile(DirIn, '*.wav')); %get file list
DirOut = fullfile(DirIn, '01');
for i = 1:length(filelist);
Filename = filelist(i).name
newStr = Filename(7:8);
if strcmp(newStr,'01')
if ~exist(DirOut)
mkdir(DirOut)
end
movefile(fullfile(filelist(i).folder, filelist(i).name), DirOut);
end
end
Firstly, you don't need eval to get the file list. eval impact performance significantly. The below is what you should have done:
filelist=dir(fullfile(DirIn, '*.wav'));
You don't need strsplit or extractBetween since you only intend to extract a part of the string by indexing, i.e. the 7th and 8th characters, you may do this:
newStr = Filename(7:8);
To use variable as an input, you need to use mkdir as a function rather than console command:
mkdir(DirOut)
Lastly, a bit of optimisation. Since DirOut is constant, you can take it outside the loop. You may also want to check if DirOut has already been created to avoid the warning message and overhead in mkdir.
There is no issue with movefile.
Couple things go wrong, first, it is not recommended to use eval. In this case you can just create a character array to pass to dir as follows:
filelist = dir([DirIn '/*.wav'])
Then, you have a strplit that appears to do nothing, since it looks like your files don't have '_' in them, so name will just return Filename. But that is not the issue, since you are using extractBetween on the Filename.
The following does not what you think it does,
mkdir DirIn DirOut
will create two directories named DirIn and DirOut in the current working directory of Matlab. To create the directories you want, use:
mkdir(DirOut)
Since the output directory did not exist before, I suspect Matlab moved the file to the input directory, and renamed it to 01, if you manually add the extension .wav it should be one of the original files.
I'd like to remove '-2' from the filenames looking like this:
EID-NFBSS-2FE454B7-2_TD.eeg
EID-NFBSS-2FE454B7-2_TD.vhdr
EID-NFBSS-2FE454B7-2_TD.vmrk
EID-NFBSS-3B3BF9FA-2_BU.eeg
EID-NFBSS-2FE454B7-2_PO.txt
So as you may see the names of the files are different and there are different kind of extensions as well. All what I want to do is remove '-2' from all of the filenames. I was trying use this:
pattern = '-2';
replacement = '';
regexprep(filename,pattern,replacement)
and I got the results in the console, but after many attempts I have no idea how to 'say' to MATLAB switch the filnames in the same location.
#excaza hit it right on the money. You'll have to probe your desired directory for a list of files via dir, then loop through each filename and remove any occurrences of -2, then use movefile to rename the file, and delete to delete the old file.
Something like this comes to mind:
%// Get all files in this directory
d = fullfile('path', 'to', 'folder', 'here');
directory = dir(d);
%// For each file in this directory...
for ii = 1 : numel(directory)
%// Get the relative filename
name = directory(ii).name;
%// Replace any instances of -2 with nothing
name_after = regexprep(name, '-2', '');
%// If the string has changed after this...
if ~strcmpi(name, name_after)
%// Get the absolute path to both the original file and
%// the new file name
fullname = fullfile(directory, name);
fullname_after = fullfile(directory, name_after);
%// Create the new file
movefile(fullname, fullname_after);
%// Delete the old file
delete(fullname);
end
end
The logic behind this is quite simple. First, the string d determines the directory where you want to search for files. fullfile is used to construct your path by parts. The reason why this is important is because this allows the code to be platform agnostic. The delineation to separate between directories is different between operating systems. For example, in Windows the character is \ while on Mac OS and Linux, it's /. I don't know which platform you're running so fullfile is going to be useful here. Simply take each part of your directory and put them in as separate strings into fullfile.
Now, use dir to find all files in this directory of your choice. Replace the /path/to/folder/here with your desired path. Next, we iterate over all of the files. For each file, we get the relative filename. dir contains information about each file, and the field you want that is most important is the name attribute. However, this attribute is relative, which means that only the filename itself, without the full path to where this file is stored is given. After, we use regexprep as you have already done to replace any instances of -2 with nothing.
The next point is important. After we try and change the filename, if the file isn't the same, we need to create a new file by simply copying the old file to a new file of the changed name and we delete the old file. The function fullfile here helps establish absolute paths to where your file is located in the off-chance that are you running this script in a directory that doesn't include the files you're looking for.
We use fullfile to find the absolute paths to both the old and new file, use movefile to create the new file and delete to delete the old file.
I am trying to read all the images in the folder in MATLAB using this code
flst=dir(str_Expfold);
But it shows me output like this. which is not the sequence as i want.
Can anyone please tell me how can i read all of them in sequence?
for giving downmark, please explain the reason for that too.
By alphabetical order depth10 comes before depth2. If at all possible, when creating string + num type filenames, use a fixed width numerical part (e.g. depth01, depth02) - this tends to avoid sorting problems.
If you are stuck with the filenames you have, and know the filename pattern, though, you can not bother using dir at all and create your filename list in the correct order in the first place:
for n = 1:50
fname = sprintf('depth%d.png',n);
% code to read and process images goes here
end
From the Matlab forums, the dir command output sorting is not specified, but it seems to be purely alphabetical order (with purely I mean that it does not take into account sorter filenames first). Therefore, you would have to manually sort the names. The following code is taken from this link (you probably want to change the file extension):
list = dir(fullfile(cd, '*.mat'));
name = {list.name};
str = sprintf('%s#', name{:});
num = sscanf(str, 'r_%d.mat#');
[dummy, index] = sort(num);
name = name(index);
So I know I can list all the files and directories in my current folder using functions like dir() or ls(), and I know once listed, I can tell them from each other with the field isdir.
But is there a way to exclude the directories from the very beggining and list the files alone?
Even better, is there a way to exclude the current . and parent .. directories -that will (of course) show everytime- and list every other file and directory? Seriously, who uses ls() wondering if . is there?
The output of dir is whatever the operating system is feeding it. So it might be different depending on what system you're running. Here is my approach to that:
list=dir();
CleanList=setdiff({list.name},{'.','..'})';
I'm not sure if there is a built in method for this, but why not write a custom function to do what you want?
Such as:
function list = files_dir(varargin)
% Similar functionality to 'dir', but only returns files (no folders)
list = dir(varargin{:});
list([list.isdir]) = [];
You can then customise this to perform other functionality, such as excluding hidden files.
And for your second request, where directories '.' and '..' are excluded:
function list = dir_exclude_self(varargin)
% same as 'dir', but doesn't return '.' or '..'
list = dir(varargin{:});
self_indices = ismember({list.name}, {'.', '..'});
list(self_indices) = [];
If you put functions like this in a specific place on your computer you can ensure they are always available to use by adding them to the MATLAB path in your startup.m file.