/
pickle.py
173 lines (142 loc) · 4.96 KB
/
pickle.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
""" pickle compat """
from io import BytesIO
import pickle
import warnings
from numpy.lib.format import read_array
from pandas.compat import pickle_compat as pc
from pandas.io.common import _get_handle, _stringify_path
def to_pickle(obj, path, compression="infer", protocol=pickle.HIGHEST_PROTOCOL):
"""
Pickle (serialize) object to file.
Parameters
----------
obj : any object
Any python object.
path : str
File path where the pickled object will be stored.
compression : {'infer', 'gzip', 'bz2', 'zip', 'xz', None}, default 'infer'
A string representing the compression to use in the output file. By
default, infers from the file extension in specified path.
.. versionadded:: 0.20.0
protocol : int
Int which indicates which protocol should be used by the pickler,
default HIGHEST_PROTOCOL (see [1], paragraph 12.1.2). The possible
values for this parameter depend on the version of Python. For Python
2.x, possible values are 0, 1, 2. For Python>=3.0, 3 is a valid value.
For Python >= 3.4, 4 is a valid value. A negative value for the
protocol parameter is equivalent to setting its value to
HIGHEST_PROTOCOL.
.. [1] https://docs.python.org/3/library/pickle.html
.. versionadded:: 0.21.0
See Also
--------
read_pickle : Load pickled pandas object (or any object) from file.
DataFrame.to_hdf : Write DataFrame to an HDF5 file.
DataFrame.to_sql : Write DataFrame to a SQL database.
DataFrame.to_parquet : Write a DataFrame to the binary parquet format.
Examples
--------
>>> original_df = pd.DataFrame({"foo": range(5), "bar": range(5, 10)})
>>> original_df
foo bar
0 0 5
1 1 6
2 2 7
3 3 8
4 4 9
>>> pd.to_pickle(original_df, "./dummy.pkl")
>>> unpickled_df = pd.read_pickle("./dummy.pkl")
>>> unpickled_df
foo bar
0 0 5
1 1 6
2 2 7
3 3 8
4 4 9
>>> import os
>>> os.remove("./dummy.pkl")
"""
path = _stringify_path(path)
f, fh = _get_handle(path, "wb", compression=compression, is_text=False)
if protocol < 0:
protocol = pickle.HIGHEST_PROTOCOL
try:
f.write(pickle.dumps(obj, protocol=protocol))
finally:
f.close()
for _f in fh:
_f.close()
def read_pickle(path, compression="infer"):
"""
Load pickled pandas object (or any object) from file.
.. warning::
Loading pickled data received from untrusted sources can be
unsafe. See `here <https://docs.python.org/3/library/pickle.html>`__.
Parameters
----------
path : str
File path where the pickled object will be loaded.
compression : {'infer', 'gzip', 'bz2', 'zip', 'xz', None}, default 'infer'
For on-the-fly decompression of on-disk data. If 'infer', then use
gzip, bz2, xz or zip if path ends in '.gz', '.bz2', '.xz',
or '.zip' respectively, and no decompression otherwise.
Set to None for no decompression.
.. versionadded:: 0.20.0
Returns
-------
unpickled : same type as object stored in file
See Also
--------
DataFrame.to_pickle : Pickle (serialize) DataFrame object to file.
Series.to_pickle : Pickle (serialize) Series object to file.
read_hdf : Read HDF5 file into a DataFrame.
read_sql : Read SQL query or database table into a DataFrame.
read_parquet : Load a parquet object, returning a DataFrame.
Notes
-----
read_pickle is only guaranteed to be backwards compatible to pandas 0.20.3.
Examples
--------
>>> original_df = pd.DataFrame({"foo": range(5), "bar": range(5, 10)})
>>> original_df
foo bar
0 0 5
1 1 6
2 2 7
3 3 8
4 4 9
>>> pd.to_pickle(original_df, "./dummy.pkl")
>>> unpickled_df = pd.read_pickle("./dummy.pkl")
>>> unpickled_df
foo bar
0 0 5
1 1 6
2 2 7
3 3 8
4 4 9
>>> import os
>>> os.remove("./dummy.pkl")
"""
path = _stringify_path(path)
f, fh = _get_handle(path, "rb", compression=compression, is_text=False)
# 1) try standard libary Pickle
# 2) try pickle_compat (older pandas version) to handle subclass changes
# 3) try pickle_compat with latin1 encoding
try:
with warnings.catch_warnings(record=True):
# We want to silence any warnings about, e.g. moved modules.
warnings.simplefilter("ignore", Warning)
return pickle.load(f)
except Exception: # noqa: E722
try:
return pc.load(f, encoding=None)
except Exception: # noqa: E722
return pc.load(f, encoding="latin1")
finally:
f.close()
for _f in fh:
_f.close()
# compat with sparse pickle / unpickle
def _unpickle_array(bytes):
arr = read_array(BytesIO(bytes))
return arr