lenskit.data.ListILC#

class lenskit.data.ListILC(key, *, index=True)#

Bases: lenskit.data._collection._base.MutableItemListCollection[lenskit.data._collection._keys.K], Generic[lenskit.data._collection._keys.K]

Mutable item list collection backed by a Python list.

Parameters:
list_schema: pyarrow.Schema#

Get the schema for the lists in this ILC.

classmethod from_dict(data: collections.abc.Mapping[lenskit.data._collection._keys.GenericKey | lenskit.data._collection._keys.ID, lenskit.data._items.ItemList], key: type[lenskit.data._collection._keys.K]) → lenskit.data._collection._base.ItemListCollection[lenskit.data._collection._keys.K]#
classmethod from_dict(data: collections.abc.Mapping[lenskit.data._collection._keys.GenericKey | lenskit.data._collection._keys.ID, lenskit.data._items.ItemList], key: collections.abc.Sequence[str] | str | None = None) → lenskit.data._collection._base.ItemListCollection[lenskit.data._collection._keys.GenericKey]

Create an item list collection from a dictionary.

classmethod from_df(df, key=None, *others)#

Create an item list collection from a data frame.

Note

Keys with empty item lists will be silently excluded from the output data.

Parameters:

  • df (pandas.DataFrame) – The data frame to convert.

  • key (type[lenskit.data._collection._keys.K] | collections.abc.Sequence[lenskit.data._adapt.Column] | lenskit.data._adapt.Column | None) – The key type or field(s). Can be specified as a single column name (or AliasedColumn).

  • others (lenskit.data._adapt.Column) – Other columns to consider; primarily used to pass additional aliased columns to normalize other clumnes like the item ID.

static from_arrow(table)#

Convert an Arrow table into an item list collection.

Parameters:

table (pyarrow.Table)

Return type:

lenskit.data._collection._base.MutableItemListCollection[Any]

add(list, *fields, **kwfields)#

Add a single item list to this list.

Parameters:

  • list (lenskit.data._items.ItemList) – The item list to add.

  • fields (lenskit.data._collection._keys.ID) – The key fields for this list.

  • kwfields (lenskit.data._collection._keys.ID) – The key fields for this list.

add_from(other, **fields)#

Add all collection from another collection to this collection. If field values are supplied, they are used to supplement or overwrite the keys in other; a common use case is to add results from multiple recommendation runs and save them a single field.

Parameters:

  • other (lenskit.data._collection._base.ItemListCollection[lenskit.data._collection._keys.Ko]) – The item list collection to incorporate into this one.

  • fields (lenskit.data._collection._keys.ID) – Additional key fields (must be specified by name).

lookup(key: tuple) → lenskit.data._items.ItemList | None#
lookup(*key: lenskit.data._collection._keys.ID, **kwkey: lenskit.data._collection._keys.ID) → lenskit.data._items.ItemList | None

Look up a list by key. If multiple lists have the same key, this returns the last (like a dictionary).

This method can be called with the key tuple as a single argument (and this can be either the actual named tuple, or an ordinary tuple of the same length), or with the individual key fields as positional or named arguments.

Parameters:

key – The key tuple or key tuple fields.

items()#

Iterate over item lists and keys.

Return type:

collections.abc.Iterator[tuple[lenskit.data._collection._keys.K, lenskit.data._items.ItemList]]

__len__()#
__getitem__(pos, /)#

Get an item list and its key by position.

Parameters:

pos (int) – The position in the list (starting from 0).

Returns:

The key and list at position pos.

Raises:

IndexError – when pos is out-of-bounds.

Return type:

tuple[lenskit.data._collection._keys.K, lenskit.data._items.ItemList]

__repr__()#