Source code for catalyst.contrib.datasets.movielens
import itertools
import os
import numpy as np
import scipy.sparse as sp
import torch
from torch.utils.data import Dataset
from catalyst.contrib.datasets.misc import download_and_extract_archive
[docs]class MovieLens(Dataset):
"""
MovieLens data sets were collected by the GroupLens Research Project
at the University of Minnesota.
This data set consists of:
* 100,000 ratings (1-5) from 943 users on 1682 movies.
* Each user has rated at least 20 movies.
* Simple demographic info for the users
(age, gender, occupation, zip)
The data was collected through the MovieLens web site
(movielens.umn.edu) during the seven-month period from September 19th,
1997 through April 22nd, 1998. This data has been cleaned up - users
who had less than 20 ratings or did not have complete demographic
information were removed from this data set. Detailed descriptions of
the data file can be found at the end of this file.
Neither the University of Minnesota nor any of the researchers
involved can guarantee the correctness of the data, its suitability
for any particular purpose, or the validity of results based on the
use of the data set. The data set may be used for any research
purposes under the following conditions:
* The user may not state or imply any endorsement from the
University of Minnesota or the GroupLens Research Group.
* The user must acknowledge the use of the data set in
publications resulting from the use of the data set
(see below for citation information).
* The user may not redistribute the data without separate
permission.
* The user may not use this information for any commercial or
revenue-bearing purposes without first obtaining permission
from a faculty member of the GroupLens Research Project at the
University of Minnesota.
If you have any further questions or comments, please contact GroupLens
<grouplens-info@cs.umn.edu>.
http://files.grouplens.org/datasets/movielens/ml-100k-README.txt
.. note::
catalyst[ml] required for this dataset.
"""
resources = (
"http://files.grouplens.org/datasets/movielens/ml-100k.zip",
"0e33842e24a9c977be4e0107933c0723",
)
filename = "ml-100k.zip"
training_file = "training.pt"
test_file = "test.pt"
[docs] def __init__(self, root, train=True, download=False, min_rating=0.0):
"""
Args:
root (string): Root directory of dataset where
``MovieLens/processed/training.pt``
and ``MovieLens/processed/test.pt`` exist.
train (bool, optional): If True, creates dataset from
``training.pt``, otherwise from ``test.pt``.
download (bool, optional): If true, downloads the dataset from
the internet and puts it in root directory. If dataset
is already downloaded, it is not downloaded again.
min_rating (float, optional): Minimum rating to include in
the interaction matrix
Raises:
RuntimeError: If ``download is False`` and the dataset not found.
"""
if isinstance(root, torch._six.string_classes):
root = os.path.expanduser(root)
self.root = root
self.train = train
self.min_rating = min_rating
if download:
self._download()
self._fetch_movies()
if not self._check_exists():
raise RuntimeError("Dataset not found. You can use download=True to download it")
if self.train:
data_file = self.training_file
else:
data_file = self.test_file
self.data = torch.load(os.path.join(self.processed_folder, data_file))
def __getitem__(self, user_index):
"""Get item.
Args:
user_index (int): User index [0, 942]
Returns:
tensor: (items) item's ranking for the user with index user_index
"""
return self.data[user_index]
def __len__(self):
"""The length of the loader"""
return self.dimensions[0]
@property
def raw_folder(self):
"""Create raw folder for data download"""
return os.path.join(self.root, self.__class__.__name__, "raw")
@property
def processed_folder(self):
"""Create the folder for the processed files"""
return os.path.join(self.root, self.__class__.__name__, "processed")
def _check_exists(self):
"""Check if the path for tarining and testing data exists in processed folder."""
return os.path.exists(
os.path.join(self.processed_folder, self.training_file)
) and os.path.exists(os.path.join(self.processed_folder, self.test_file))
def _download(self):
"""Download and extract files/"""
if self._check_exists():
return
os.makedirs(self.raw_folder, exist_ok=True)
os.makedirs(self.processed_folder, exist_ok=True)
url = self.resources[0]
md5 = self.resources[1]
download_and_extract_archive(
url=url,
download_root=self.raw_folder,
filename=self.filename,
md5=md5,
remove_finished=True,
)
def _read_raw_movielens_data(self):
"""Return the raw lines of the train and test files."""
path = self.raw_folder
with open(path + "/ml-100k/ua.base") as datafile:
ua_base = datafile.read().split("\n")
with open(path + "/ml-100k/ua.test") as datafile:
ua_test = datafile.read().split("\n")
with open(path + "/ml-100k/u.item", encoding="ISO-8859-1") as datafile:
u_item = datafile.read().split("\n")
with open(path + "/ml-100k/u.genre") as datafile:
u_genre = datafile.read().split("\n")
return (ua_base, ua_test, u_item, u_genre)
def _build_interaction_matrix(self, rows, cols, data):
"""Builds interaction matrix.
Args:
rows (int): rows of the oevrall dataset
cols (int): columns of the overall dataset
data (generator object): generator of
the data object
Returns:
interaction_matrix (torch.sparse.Float):
sparse user2item interaction matrix
"""
mat = sp.lil_matrix((rows, cols), dtype=np.int32)
for uid, iid, rating, _ in data:
if rating >= self.min_rating:
mat[uid, iid] = rating
coo = mat.tocoo()
values = coo.data
indices = np.vstack((coo.row, coo.col))
i = torch.LongTensor(indices)
v = torch.FloatTensor(values)
shape = coo.shape
interaction_matrix = torch.sparse.FloatTensor(i, v, torch.Size(shape)).to_dense()
return interaction_matrix
def _parse(self, data):
"""Parses the raw data. Substract one to shift to zero based indexing
Args:
data: raw data of the dataset
Yields:
Generator iterator for parsed data
"""
for line in data:
if not line:
continue
uid, iid, rating, timestamp = [int(x) for x in line.split("\t")]
yield uid - 1, iid - 1, rating, timestamp
def _get_dimensions(self, train_data, test_data):
"""Gets the dimensions of the raw dataset
Args:
train_data: (uid, iid, rating, timestamp)
Genrator for training data
test_data: (uid, iid, rating, timestamp)
Genrator for testing data
Returns:
The total dimension of the dataset
"""
uids = set()
iids = set()
for uid, iid, _, _ in itertools.chain(train_data, test_data):
uids.add(uid)
iids.add(iid)
rows = max(uids) + 1
cols = max(iids) + 1
self.dimensions = (rows, cols)
return rows, cols
def _fetch_movies(self):
"""
Fetch data and save in the pytorch format
1. Read the train/test data from raw archive
2. Parse train data
3. Parse test data
4. Save in the .pt with torch.save
"""
(train_raw, test_raw, item_metadata_raw, genres_raw) = self._read_raw_movielens_data()
num_users, num_items = self._get_dimensions(self._parse(train_raw), self._parse(test_raw))
train = self._build_interaction_matrix(num_users, num_items, self._parse(train_raw))
test = self._build_interaction_matrix(num_users, num_items, self._parse(test_raw))
assert train.shape == test.shape
with open(os.path.join(self.processed_folder, self.training_file), "wb") as f:
torch.save(train, f)
with open(os.path.join(self.processed_folder, self.test_file), "wb") as f:
torch.save(test, f)
__all__ = ["MovieLens"]