dataset module

The dataset module defines the Dataset class and other subclasses which are used for managing datasets.

Users may use both built-in and user-defined datasets (see the Getting Started page for examples). Right now, three built-in datasets are available:

• The movielens-100k dataset.

• The movielens-1m dataset.

• The Jester dataset 2.

Built-in datasets can all be loaded (or downloaded if you haven’t already) using the Dataset.load_builtin() method. Summary:

Dataset.load_builtin	Load a built-in dataset.
Dataset.load_from_file	Load a dataset from a (custom) file.
Dataset.load_from_folds	Load a dataset where folds (for cross-validation) are predefined by some files.

class surprise.dataset.Dataset(reader)

Base class for loading datasets.

Note that you should never instantiate the Dataset class directly (same goes for its derived classes), but instead use one of the three available methods for loading datasets.

classmethod load_builtin(name='ml-100k', prompt=True)

Load a built-in dataset.

If the dataset has not already been loaded, it will be downloaded and saved. You will have to split your dataset using the split method. See an example in the User Guide.

Parameters:

• name (string) – The name of the built-in dataset to load. Accepted values are ‘ml-100k’, ‘ml-1m’, and ‘jester’. Default is ‘ml-100k’.

• prompt (bool) – Prompt before downloading if dataset is not already on disk. Default is True.

Returns:

A Dataset object.

Raises:

ValueError – If the name parameter is incorrect.

classmethod load_from_df(df, reader)

Load a dataset from a pandas dataframe.

Use this if you want to use a custom dataset that is stored in a pandas dataframe. See the User Guide for an example.

Parameters:

• df (Dataframe) – The dataframe containing the ratings. It must have three columns, corresponding to the user (raw) ids, the item (raw) ids, and the ratings, in this order.

• reader (Reader) – A reader to read the file. Only the rating_scale field needs to be specified.

classmethod load_from_file(file_path, reader)

Load a dataset from a (custom) file.

Use this if you want to use a custom dataset and all of the ratings are stored in one file. You will have to split your dataset using the split method. See an example in the User Guide.

Parameters:

• file_path (string) – The path to the file containing ratings.

• reader (Reader) – A reader to read the file.

classmethod load_from_folds(folds_files, reader)

Load a dataset where folds (for cross-validation) are predefined by some files.

The purpose of this method is to cover a common use case where a dataset is already split into predefined folds, such as the movielens-100k dataset which defines files u1.base, u1.test, u2.base, u2.test, etc… It can also be used when you don’t want to perform cross-validation but still want to specify your training and testing data (which comes down to 1-fold cross-validation anyway). See an example in the User Guide.

Parameters:

• folds_files (iterable of tuples) – The list of the folds. A fold is a tuple of the form (path_to_train_file, path_to_test_file).

• reader (Reader) – A reader to read the files.

class surprise.dataset.DatasetAutoFolds(ratings_file=None, reader=None, df=None)

A derived class from Dataset for which folds (for cross-validation) are not predefined. (Or for when there are no folds at all).

build_full_trainset()

Do not split the dataset into folds and just return a trainset as is, built from the whole dataset.

User can then query for predictions, as shown in the User Guide.

Returns:

The Trainset.