numpy.lib.npyio.NpzFile#
- class numpy.lib.npyio.NpzFile(fid)[source]#
A dictionary-like object with lazy-loading of files in the zipped archive provided on construction.
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 usingobj.f.key
. A list of all files (without.npy
extensions) can be obtained withobj.files
and the ZipFile object itself usingobj.zip
.- Parameters:
- fidfile, 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_fidbool, optional
Whether NpzFile should close the file handle. Requires that
fid
is a file-like object.
Examples
>>> 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) True >>> npz NpzFile 'object' with keys: x, y >>> sorted(npz.files) ['x', 'y'] >>> npz['x'] # getitem access array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]) >>> npz.f.x # attribute lookup array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])
- Attributes:
- fileslist of str
List of all files in the archive with a
.npy
extension.- zipZipFile instance
The ZipFile object initialized with the zipped archive.
- fBagObj instance
An object on which attribute can be performed as an alternative to getitem access on the
NpzFile
instance itself.- allow_picklebool, optional
Allow loading pickled data. Default: False
Changed in version 1.16.3: Made default False in response to CVE-2019-6446.
- pickle_kwargsdict, optional
Additional keyword arguments to pass on to pickle.load. These are only useful when loading object arrays saved on Python 2 when using Python 3.
- max_header_sizeint, 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.
Methods
close
()Close the file.
get
(key[, default])D.get(k,[,d]) returns D[k] if k in D, else d.
items
()D.items() returns a set-like object providing a view on the items
keys
()D.keys() returns a set-like object providing a view on the keys
values
()D.values() returns a set-like object providing a view on the values