![]() > lm1, type(lm1) # Empty list now - generator already exhausted ![]() ![]() > lm1 = list(m) # Build a list from the same generator > lm0 = list(m) # Build a list from the generator TypeError: object of type 'map' has no len() > m = map(lambda x: x, ) # Just a dummy lambda function The example below illustrates the differences on : Built-in functions - map(function, iterable, *iterables) Not sure if returning a list is still mandatory (or a generator would do as well), but passing a generator to the list constructor, will create a list out of it (and also consume it). In Python 3, generator is the default behavior As time passed, generator counterparts started to appear for functions that returned / worked with lists In Python 2.2, the concept of generator ( : Generators) - courtesy of : Simple statements - The yield statement) - was introduced. In pre Python 2.2 versions, sequences (iterables) were mostly represented by lists (tuples, sets. That has consequences related to another keyword in the question: " add them into a list": 5) (I'll keep them as Python 2 compliant as possible also, any code belonging to Python that I'm going to post, is from v3.5.4 - unless otherwise specified). When the question was asked, I imagine that Python 2, was the LTS version, however the code samples will be run by Python 3(. The statement: " all files of a directory" can be interpreted in two ways:Īll descendants in the whole directory tree (including the ones in sub-directories) Users/johnny/Desktop/TEST/SUBFOLDER/file3.datĪlthough there's a clear differentiation between file and directory terms in the question text, some may argue that directories are actually special files If you'd like, you can open and read the contents, or focus only on files with the extension ".dat" like in the code below: for f in full_file_paths: Print full_file_paths which will print the list: The path I provided in the above function contained 3 files- two of them in the root directory, and another in a subfolder called "SUBFOLDER." You can now do things like:.# Run the above function and store its results in a variable.įull_file_paths = get_filepaths("/Users/johnny/Desktop/TEST") # Join the two strings in order to form the full filepath.įile_paths.append(filepath) # Add it to the list. It yields a 3-tuple (dirpath, dirnames, filenames).įile_paths = # List which will store all of the full filepaths.įor root, directories, files in os.walk(directory): For eachĭirectory in the tree rooted at directory top (including top itself), Tree by walking the tree either top-down or bottom-up. This function will generate the file names in a directory Getting Full File Paths From a Directory and All Its Subdirectories import os # In this case, it shows the files only in the current directory # This one is more efficient than `os.listdir`. # Another example with `scandir` (a little variation from ) Os.scandir() from Python 3.5 and greater import os Get all the subdir names with walk for r,d,f in os.walk("F:\\_python"): Next(os.walk('F://python')) # for the current dir use ('.') Get only directories with next and walk in a directory, because in the element there are the folders only import os Get only files with next in a directory: returns only the file in the root folder import os Get all and only files with os.walk: checks only in the third element returned, i.e. Use glob method in pathlib.Path() import pathlib Using pathlib from Python 3.4 import pathlib Using os.path.isfile to avoid directories in the list import os.path Using glob to get the full path of the files from path import path Os.listdir() - get only txt files arr_txt = Os.walk('.') - current directory import os Get files of a particular subdirectory with os.listdir() import os To go up in the directory tree # Method 1 # Getting the current work directory (cwd) Os.walk returns the root, the directories list and the files list, that is why I unpacked them in r, d, f in the for loop it, then, looks for other files and directories in the subfolders of the root and so on until there are no subfolders. You get the full path in return import osįiles_path = Getting the full path name with os.path.abspath Onlyfiles = [os.path.join(cwd, f) for f in os.listdir(cwd) if Get the full path of only files in the current directory import os With glob you can specify a type of file to list like this import glob Looking in a directory arr = os.listdir('c:\\files') With listdir in os module you get the files and the folders in the current dir import os
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