kedro.io.PickleLocalDataSet¶
-
class
kedro.io.
PickleLocalDataSet
(filepath, backend='pickle', load_args=None, save_args=None, version=None)[source]¶ PickleLocalDataSet
loads and saves a Python object to a local pickle file. The underlying functionality is supported by the pickle and joblib libraries, so it supports all allowed options for loading and saving pickle files.Example:
from kedro.io import PickleLocalDataSet import pandas as pd dummy_data = pd.DataFrame({'col1': [1, 2], 'col2': [4, 5], 'col3': [5, 6]}) data_set = PickleLocalDataSet(filepath="data.pkl", backend='pickle', load_args=None, save_args=None) data_set.save(dummy_data) reloaded = data_set.load()
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__init__
(filepath, backend='pickle', load_args=None, save_args=None, version=None)[source]¶ Creates a new instance of
PickleLocalDataSet
pointing to a concrete filepath.PickleLocalDataSet
can use two backends to serialise objects to disk:pickle.dump: https://docs.python.org/3/library/pickle.html#pickle.dump
joblib.dump: https://pythonhosted.org/joblib/generated/joblib.dump.html
and it can use two backends to load serialised objects into memory:
pickle.load: https://docs.python.org/3/library/pickle.html#pickle.load
joblib.load: https://pythonhosted.org/joblib/generated/joblib.load.html
Joblib tends to exhibit better performance in case objects store NumPy arrays: http://gael-varoquaux.info/programming/new_low-overhead_persistence_in_joblib_for_big_data.html.
Parameters: - filepath (
str
) – path to a pkl file. - backend (
str
) – backend to use, must be one of [‘pickle’, ‘joblib’]. - load_args (
Optional
[Dict
[str
,Any
]]) – Options for loading pickle files. Refer to the help file ofpickle.load
orjoblib.load
for options. - save_args (
Optional
[Dict
[str
,Any
]]) – Options for saving pickle files. Refer to the help file ofpickle.dump
orjoblib.load
for options. - version (
Optional
[Version
]) – If specified, should be an instance ofkedro.io.core.Version
. If itsload
attribute is None, the latest version will be loaded. If itssave
attribute is None, save version will be autogenerated.
Raises: ValueError
– If ‘backend’ is not one of [‘pickle’, ‘joblib’].ImportError
– If ‘backend’ could not be imported.
Return type: None
- filepath (
Methods
__init__
(filepath[, backend, load_args, …])Creates a new instance of PickleLocalDataSet
pointing to a concrete filepath.exists
()Checks whether a data set’s output already exists by calling the provided _exists() method. from_config
(name, config[, load_version, …])Create a data set instance using the configuration provided. load
()Loads data by delegation to the provided load method. save
(data)Saves data by delegation to the provided save method. Attributes
BACKENDS
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