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models – Package for transformation models

models – Package for transformation models

This package contains algorithms for extracting document representations from their raw bag-of-word counts.

class gensim.models.VocabTransform(old2new, id2token=None)

Remap feature ids to new values.

Given a mapping between old ids and new ids (some old ids may be missing = these features are to be discarded), this will wrap a corpus so that iterating over VocabTransform[corpus] returns the same vectors but with the new ids.

Old features that have no counterpart in the new ids are discarded. This can be used to filter vocabulary of a corpus “online”:

>>> old2new = {oldid: newid for newid, oldid in enumerate(ids_you_want_to_keep)}
>>> vt = VocabTransform(old2new)
>>> for vec_with_new_ids in vt[corpus_with_old_ids]:
>>>     pass
classmethod load(fname, mmap=None)

Load an object previously saved using save() from a file.

  • fname (str) – Path to file that contains needed object.

  • mmap (str, optional) – Memory-map option. If the object was saved with large arrays stored separately, you can load these arrays via mmap (shared memory) using mmap=’r’. If the file being loaded is compressed (either ‘.gz’ or ‘.bz2’), then `mmap=None must be set.

See also


Save object to file.


Object loaded from fname.

Return type



AttributeError – When called on an object instance instead of class (this is a class method).

save(fname_or_handle, separately=None, sep_limit=10485760, ignore=frozenset({}), pickle_protocol=2)

Save the object to a file.

  • fname_or_handle (str or file-like) – Path to output file or already opened file-like object. If the object is a file handle, no special array handling will be performed, all attributes will be saved to the same file.

  • separately (list of str or None, optional) –

    If None, automatically detect large numpy/scipy.sparse arrays in the object being stored, and store them into separate files. This prevent memory errors for large objects, and also allows memory-mapping the large arrays for efficient loading and sharing the large arrays in RAM between multiple processes.

    If list of str: store these attributes into separate files. The automated size check is not performed in this case.

  • sep_limit (int, optional) – Don’t store arrays smaller than this separately. In bytes.

  • ignore (frozenset of str, optional) – Attributes that shouldn’t be stored at all.

  • pickle_protocol (int, optional) – Protocol number for pickle.

See also


Load object from file.