`numpy.lib.npyio:NpzFile`

source: build-install/usr/lib/python3.14/site-packages/numpy/lib/npyio.py

Signature

def NpzFile ( fid )

Summary

A dictionary-like object with lazy-loading of files in the zipped archive provided on construction.

Extended Summary

NpzFile is used to load files in the NumPy .npz data archive format. It assumes that files in the archive have a .npy extension, other files are ignored.

The arrays and file strings are lazily loaded on either getitem access using obj['key'] or attribute lookup using obj.f.key. A list of all files (without .npy extensions) can be obtained with obj.files and the ZipFile object itself using obj.zip.

Parameters

fid : file, str, or pathlib.Path: The zipped archive to open. This is either a file-like object or a string containing the path to the archive.
own_fid : bool, optional: Whether NpzFile should close the file handle. Requires that fid is a file-like object.

Attributes

files : list of str: List of all files in the archive with a .npy extension.
zip : ZipFile instance: The ZipFile object initialized with the zipped archive.
f : BagObj instance: An object on which attribute can be performed as an alternative to getitem access on the NpzFile instance itself.
allow_pickle : bool, optional: Allow loading pickled data. Default: False
pickle_kwargs : dict, optional: Additional keyword arguments to pass on to pickle.load. These are only useful when loading object arrays saved on Python 2.
max_header_size : int, optional: Maximum allowed size of the header. Large headers may not be safe to load securely and thus require explicitly passing a larger value. See ast.literal_eval() for details. This option is ignored when allow_pickle is passed. In that case the file is by definition trusted and the limit is unnecessary.

Examples

import numpy as np
from tempfile import TemporaryFile
outfile = TemporaryFile()
x = np.arange(10)
y = np.sin(x)
np.savez(outfile, x=x, y=y)
_ = outfile.seek(0)

✓

npz = np.load(outfile)
isinstance(npz, np.lib.npyio.NpzFile)
npz
sorted(npz.files)
npz['x']  # getitem access
npz.f.x  # attribute lookup

✓

Aliases

numpy.lib._npyio_impl.NpzFile