Inzynierka/Lib/site-packages/pandas/core/shared_docs.py

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from __future__ import annotations
_shared_docs: dict[str, str] = {}
_shared_docs[
"aggregate"
] = """
Aggregate using one or more operations over the specified axis.
Parameters
----------
func : function, str, list or dict
Function to use for aggregating the data. If a function, must either
work when passed a {klass} or when passed to {klass}.apply.
Accepted combinations are:
- function
- string function name
- list of functions and/or function names, e.g. ``[np.sum, 'mean']``
- dict of axis labels -> functions, function names or list of such.
{axis}
*args
Positional arguments to pass to `func`.
**kwargs
Keyword arguments to pass to `func`.
Returns
-------
scalar, Series or DataFrame
The return can be:
* scalar : when Series.agg is called with single function
* Series : when DataFrame.agg is called with a single function
* DataFrame : when DataFrame.agg is called with several functions
Return scalar, Series or DataFrame.
{see_also}
Notes
-----
`agg` is an alias for `aggregate`. Use the alias.
Functions that mutate the passed object can produce unexpected
behavior or errors and are not supported. See :ref:`gotchas.udf-mutation`
for more details.
A passed user-defined-function will be passed a Series for evaluation.
{examples}"""
_shared_docs[
"compare"
] = """
Compare to another {klass} and show the differences.
.. versionadded:: 1.1.0
Parameters
----------
other : {klass}
Object to compare with.
align_axis : {{0 or 'index', 1 or 'columns'}}, default 1
Determine which axis to align the comparison on.
* 0, or 'index' : Resulting differences are stacked vertically
with rows drawn alternately from self and other.
* 1, or 'columns' : Resulting differences are aligned horizontally
with columns drawn alternately from self and other.
keep_shape : bool, default False
If true, all rows and columns are kept.
Otherwise, only the ones with different values are kept.
keep_equal : bool, default False
If true, the result keeps values that are equal.
Otherwise, equal values are shown as NaNs.
result_names : tuple, default ('self', 'other')
Set the dataframes names in the comparison.
.. versionadded:: 1.5.0
"""
_shared_docs[
"groupby"
] = """
Group %(klass)s using a mapper or by a Series of columns.
A groupby operation involves some combination of splitting the
object, applying a function, and combining the results. This can be
used to group large amounts of data and compute operations on these
groups.
Parameters
----------
by : mapping, function, label, pd.Grouper or list of such
Used to determine the groups for the groupby.
If ``by`` is a function, it's called on each value of the object's
index. If a dict or Series is passed, the Series or dict VALUES
will be used to determine the groups (the Series' values are first
aligned; see ``.align()`` method). If a list or ndarray of length
equal to the selected axis is passed (see the `groupby user guide
<https://pandas.pydata.org/pandas-docs/stable/user_guide/groupby.html#splitting-an-object-into-groups>`_),
the values are used as-is to determine the groups. A label or list
of labels may be passed to group by the columns in ``self``.
Notice that a tuple is interpreted as a (single) key.
axis : {0 or 'index', 1 or 'columns'}, default 0
Split along rows (0) or columns (1). For `Series` this parameter
is unused and defaults to 0.
level : int, level name, or sequence of such, default None
If the axis is a MultiIndex (hierarchical), group by a particular
level or levels. Do not specify both ``by`` and ``level``.
as_index : bool, default True
For aggregated output, return object with group labels as the
index. Only relevant for DataFrame input. as_index=False is
effectively "SQL-style" grouped output.
sort : bool, default True
Sort group keys. Get better performance by turning this off.
Note this does not influence the order of observations within each
group. Groupby preserves the order of rows within each group.
.. versionchanged:: 2.0.0
Specifying ``sort=False`` with an ordered categorical grouper will no
longer sort the values.
group_keys : bool, default True
When calling apply and the ``by`` argument produces a like-indexed
(i.e. :ref:`a transform <groupby.transform>`) result, add group keys to
index to identify pieces. By default group keys are not included
when the result's index (and column) labels match the inputs, and
are included otherwise.
.. versionchanged:: 1.5.0
Warns that ``group_keys`` will no longer be ignored when the
result from ``apply`` is a like-indexed Series or DataFrame.
Specify ``group_keys`` explicitly to include the group keys or
not.
.. versionchanged:: 2.0.0
``group_keys`` now defaults to ``True``.
observed : bool, default False
This only applies if any of the groupers are Categoricals.
If True: only show observed values for categorical groupers.
If False: show all values for categorical groupers.
dropna : bool, default True
If True, and if group keys contain NA values, NA values together
with row/column will be dropped.
If False, NA values will also be treated as the key in groups.
.. versionadded:: 1.1.0
Returns
-------
%(klass)sGroupBy
Returns a groupby object that contains information about the groups.
See Also
--------
resample : Convenience method for frequency conversion and resampling
of time series.
Notes
-----
See the `user guide
<https://pandas.pydata.org/pandas-docs/stable/groupby.html>`__ for more
detailed usage and examples, including splitting an object into groups,
iterating through groups, selecting a group, aggregation, and more.
"""
_shared_docs[
"melt"
] = """
Unpivot a DataFrame from wide to long format, optionally leaving identifiers set.
This function is useful to massage a DataFrame into a format where one
or more columns are identifier variables (`id_vars`), while all other
columns, considered measured variables (`value_vars`), are "unpivoted" to
the row axis, leaving just two non-identifier columns, 'variable' and
'value'.
Parameters
----------
id_vars : tuple, list, or ndarray, optional
Column(s) to use as identifier variables.
value_vars : tuple, list, or ndarray, optional
Column(s) to unpivot. If not specified, uses all columns that
are not set as `id_vars`.
var_name : scalar
Name to use for the 'variable' column. If None it uses
``frame.columns.name`` or 'variable'.
value_name : scalar, default 'value'
Name to use for the 'value' column.
col_level : int or str, optional
If columns are a MultiIndex then use this level to melt.
ignore_index : bool, default True
If True, original index is ignored. If False, the original index is retained.
Index labels will be repeated as necessary.
.. versionadded:: 1.1.0
Returns
-------
DataFrame
Unpivoted DataFrame.
See Also
--------
%(other)s : Identical method.
pivot_table : Create a spreadsheet-style pivot table as a DataFrame.
DataFrame.pivot : Return reshaped DataFrame organized
by given index / column values.
DataFrame.explode : Explode a DataFrame from list-like
columns to long format.
Notes
-----
Reference :ref:`the user guide <reshaping.melt>` for more examples.
Examples
--------
>>> df = pd.DataFrame({'A': {0: 'a', 1: 'b', 2: 'c'},
... 'B': {0: 1, 1: 3, 2: 5},
... 'C': {0: 2, 1: 4, 2: 6}})
>>> df
A B C
0 a 1 2
1 b 3 4
2 c 5 6
>>> %(caller)sid_vars=['A'], value_vars=['B'])
A variable value
0 a B 1
1 b B 3
2 c B 5
>>> %(caller)sid_vars=['A'], value_vars=['B', 'C'])
A variable value
0 a B 1
1 b B 3
2 c B 5
3 a C 2
4 b C 4
5 c C 6
The names of 'variable' and 'value' columns can be customized:
>>> %(caller)sid_vars=['A'], value_vars=['B'],
... var_name='myVarname', value_name='myValname')
A myVarname myValname
0 a B 1
1 b B 3
2 c B 5
Original index values can be kept around:
>>> %(caller)sid_vars=['A'], value_vars=['B', 'C'], ignore_index=False)
A variable value
0 a B 1
1 b B 3
2 c B 5
0 a C 2
1 b C 4
2 c C 6
If you have multi-index columns:
>>> df.columns = [list('ABC'), list('DEF')]
>>> df
A B C
D E F
0 a 1 2
1 b 3 4
2 c 5 6
>>> %(caller)scol_level=0, id_vars=['A'], value_vars=['B'])
A variable value
0 a B 1
1 b B 3
2 c B 5
>>> %(caller)sid_vars=[('A', 'D')], value_vars=[('B', 'E')])
(A, D) variable_0 variable_1 value
0 a B E 1
1 b B E 3
2 c B E 5
"""
_shared_docs[
"transform"
] = """
Call ``func`` on self producing a {klass} with the same axis shape as self.
Parameters
----------
func : function, str, list-like or dict-like
Function to use for transforming the data. If a function, must either
work when passed a {klass} or when passed to {klass}.apply. If func
is both list-like and dict-like, dict-like behavior takes precedence.
Accepted combinations are:
- function
- string function name
- list-like of functions and/or function names, e.g. ``[np.exp, 'sqrt']``
- dict-like of axis labels -> functions, function names or list-like of such.
{axis}
*args
Positional arguments to pass to `func`.
**kwargs
Keyword arguments to pass to `func`.
Returns
-------
{klass}
A {klass} that must have the same length as self.
Raises
------
ValueError : If the returned {klass} has a different length than self.
See Also
--------
{klass}.agg : Only perform aggregating type operations.
{klass}.apply : Invoke function on a {klass}.
Notes
-----
Functions that mutate the passed object can produce unexpected
behavior or errors and are not supported. See :ref:`gotchas.udf-mutation`
for more details.
Examples
--------
>>> df = pd.DataFrame({{'A': range(3), 'B': range(1, 4)}})
>>> df
A B
0 0 1
1 1 2
2 2 3
>>> df.transform(lambda x: x + 1)
A B
0 1 2
1 2 3
2 3 4
Even though the resulting {klass} must have the same length as the
input {klass}, it is possible to provide several input functions:
>>> s = pd.Series(range(3))
>>> s
0 0
1 1
2 2
dtype: int64
>>> s.transform([np.sqrt, np.exp])
sqrt exp
0 0.000000 1.000000
1 1.000000 2.718282
2 1.414214 7.389056
You can call transform on a GroupBy object:
>>> df = pd.DataFrame({{
... "Date": [
... "2015-05-08", "2015-05-07", "2015-05-06", "2015-05-05",
... "2015-05-08", "2015-05-07", "2015-05-06", "2015-05-05"],
... "Data": [5, 8, 6, 1, 50, 100, 60, 120],
... }})
>>> df
Date Data
0 2015-05-08 5
1 2015-05-07 8
2 2015-05-06 6
3 2015-05-05 1
4 2015-05-08 50
5 2015-05-07 100
6 2015-05-06 60
7 2015-05-05 120
>>> df.groupby('Date')['Data'].transform('sum')
0 55
1 108
2 66
3 121
4 55
5 108
6 66
7 121
Name: Data, dtype: int64
>>> df = pd.DataFrame({{
... "c": [1, 1, 1, 2, 2, 2, 2],
... "type": ["m", "n", "o", "m", "m", "n", "n"]
... }})
>>> df
c type
0 1 m
1 1 n
2 1 o
3 2 m
4 2 m
5 2 n
6 2 n
>>> df['size'] = df.groupby('c')['type'].transform(len)
>>> df
c type size
0 1 m 3
1 1 n 3
2 1 o 3
3 2 m 4
4 2 m 4
5 2 n 4
6 2 n 4
"""
_shared_docs[
"storage_options"
] = """storage_options : dict, optional
Extra options that make sense for a particular storage connection, e.g.
host, port, username, password, etc. For HTTP(S) URLs the key-value pairs
are forwarded to ``urllib.request.Request`` as header options. For other
URLs (e.g. starting with "s3://", and "gcs://") the key-value pairs are
forwarded to ``fsspec.open``. Please see ``fsspec`` and ``urllib`` for more
details, and for more examples on storage options refer `here
<https://pandas.pydata.org/docs/user_guide/io.html?
highlight=storage_options#reading-writing-remote-files>`_."""
_shared_docs[
"compression_options"
] = """compression : str or dict, default 'infer'
For on-the-fly compression of the output data. If 'infer' and '%s' is
path-like, then detect compression from the following extensions: '.gz',
'.bz2', '.zip', '.xz', '.zst', '.tar', '.tar.gz', '.tar.xz' or '.tar.bz2'
(otherwise no compression).
Set to ``None`` for no compression.
Can also be a dict with key ``'method'`` set
to one of {``'zip'``, ``'gzip'``, ``'bz2'``, ``'zstd'``, ``'tar'``} and other
key-value pairs are forwarded to
``zipfile.ZipFile``, ``gzip.GzipFile``,
``bz2.BZ2File``, ``zstandard.ZstdCompressor`` or
``tarfile.TarFile``, respectively.
As an example, the following could be passed for faster compression and to create
a reproducible gzip archive:
``compression={'method': 'gzip', 'compresslevel': 1, 'mtime': 1}``.
.. versionadded:: 1.5.0
Added support for `.tar` files."""
_shared_docs[
"decompression_options"
] = """compression : str or dict, default 'infer'
For on-the-fly decompression of on-disk data. If 'infer' and '%s' is
path-like, then detect compression from the following extensions: '.gz',
'.bz2', '.zip', '.xz', '.zst', '.tar', '.tar.gz', '.tar.xz' or '.tar.bz2'
(otherwise no compression).
If using 'zip' or 'tar', the ZIP file must contain only one data file to be read in.
Set to ``None`` for no decompression.
Can also be a dict with key ``'method'`` set
to one of {``'zip'``, ``'gzip'``, ``'bz2'``, ``'zstd'``, ``'tar'``} and other
key-value pairs are forwarded to
``zipfile.ZipFile``, ``gzip.GzipFile``,
``bz2.BZ2File``, ``zstandard.ZstdDecompressor`` or
``tarfile.TarFile``, respectively.
As an example, the following could be passed for Zstandard decompression using a
custom compression dictionary:
``compression={'method': 'zstd', 'dict_data': my_compression_dict}``.
.. versionadded:: 1.5.0
Added support for `.tar` files."""
_shared_docs[
"replace"
] = """
Replace values given in `to_replace` with `value`.
Values of the {klass} are replaced with other values dynamically.
{replace_iloc}
Parameters
----------
to_replace : str, regex, list, dict, Series, int, float, or None
How to find the values that will be replaced.
* numeric, str or regex:
- numeric: numeric values equal to `to_replace` will be
replaced with `value`
- str: string exactly matching `to_replace` will be replaced
with `value`
- regex: regexs matching `to_replace` will be replaced with
`value`
* list of str, regex, or numeric:
- First, if `to_replace` and `value` are both lists, they
**must** be the same length.
- Second, if ``regex=True`` then all of the strings in **both**
lists will be interpreted as regexs otherwise they will match
directly. This doesn't matter much for `value` since there
are only a few possible substitution regexes you can use.
- str, regex and numeric rules apply as above.
* dict:
- Dicts can be used to specify different replacement values
for different existing values. For example,
``{{'a': 'b', 'y': 'z'}}`` replaces the value 'a' with 'b' and
'y' with 'z'. To use a dict in this way, the optional `value`
parameter should not be given.
- For a DataFrame a dict can specify that different values
should be replaced in different columns. For example,
``{{'a': 1, 'b': 'z'}}`` looks for the value 1 in column 'a'
and the value 'z' in column 'b' and replaces these values
with whatever is specified in `value`. The `value` parameter
should not be ``None`` in this case. You can treat this as a
special case of passing two lists except that you are
specifying the column to search in.
- For a DataFrame nested dictionaries, e.g.,
``{{'a': {{'b': np.nan}}}}``, are read as follows: look in column
'a' for the value 'b' and replace it with NaN. The optional `value`
parameter should not be specified to use a nested dict in this
way. You can nest regular expressions as well. Note that
column names (the top-level dictionary keys in a nested
dictionary) **cannot** be regular expressions.
* None:
- This means that the `regex` argument must be a string,
compiled regular expression, or list, dict, ndarray or
Series of such elements. If `value` is also ``None`` then
this **must** be a nested dictionary or Series.
See the examples section for examples of each of these.
value : scalar, dict, list, str, regex, default None
Value to replace any values matching `to_replace` with.
For a DataFrame a dict of values can be used to specify which
value to use for each column (columns not in the dict will not be
filled). Regular expressions, strings and lists or dicts of such
objects are also allowed.
{inplace}
limit : int, default None
Maximum size gap to forward or backward fill.
regex : bool or same types as `to_replace`, default False
Whether to interpret `to_replace` and/or `value` as regular
expressions. If this is ``True`` then `to_replace` *must* be a
string. Alternatively, this could be a regular expression or a
list, dict, or array of regular expressions in which case
`to_replace` must be ``None``.
method : {{'pad', 'ffill', 'bfill'}}
The method to use when for replacement, when `to_replace` is a
scalar, list or tuple and `value` is ``None``.
Returns
-------
{klass}
Object after replacement.
Raises
------
AssertionError
* If `regex` is not a ``bool`` and `to_replace` is not
``None``.
TypeError
* If `to_replace` is not a scalar, array-like, ``dict``, or ``None``
* If `to_replace` is a ``dict`` and `value` is not a ``list``,
``dict``, ``ndarray``, or ``Series``
* If `to_replace` is ``None`` and `regex` is not compilable
into a regular expression or is a list, dict, ndarray, or
Series.
* When replacing multiple ``bool`` or ``datetime64`` objects and
the arguments to `to_replace` does not match the type of the
value being replaced
ValueError
* If a ``list`` or an ``ndarray`` is passed to `to_replace` and
`value` but they are not the same length.
See Also
--------
{klass}.fillna : Fill NA values.
{klass}.where : Replace values based on boolean condition.
Series.str.replace : Simple string replacement.
Notes
-----
* Regex substitution is performed under the hood with ``re.sub``. The
rules for substitution for ``re.sub`` are the same.
* Regular expressions will only substitute on strings, meaning you
cannot provide, for example, a regular expression matching floating
point numbers and expect the columns in your frame that have a
numeric dtype to be matched. However, if those floating point
numbers *are* strings, then you can do this.
* This method has *a lot* of options. You are encouraged to experiment
and play with this method to gain intuition about how it works.
* When dict is used as the `to_replace` value, it is like
key(s) in the dict are the to_replace part and
value(s) in the dict are the value parameter.
Examples
--------
**Scalar `to_replace` and `value`**
>>> s = pd.Series([1, 2, 3, 4, 5])
>>> s.replace(1, 5)
0 5
1 2
2 3
3 4
4 5
dtype: int64
>>> df = pd.DataFrame({{'A': [0, 1, 2, 3, 4],
... 'B': [5, 6, 7, 8, 9],
... 'C': ['a', 'b', 'c', 'd', 'e']}})
>>> df.replace(0, 5)
A B C
0 5 5 a
1 1 6 b
2 2 7 c
3 3 8 d
4 4 9 e
**List-like `to_replace`**
>>> df.replace([0, 1, 2, 3], 4)
A B C
0 4 5 a
1 4 6 b
2 4 7 c
3 4 8 d
4 4 9 e
>>> df.replace([0, 1, 2, 3], [4, 3, 2, 1])
A B C
0 4 5 a
1 3 6 b
2 2 7 c
3 1 8 d
4 4 9 e
>>> s.replace([1, 2], method='bfill')
0 3
1 3
2 3
3 4
4 5
dtype: int64
**dict-like `to_replace`**
>>> df.replace({{0: 10, 1: 100}})
A B C
0 10 5 a
1 100 6 b
2 2 7 c
3 3 8 d
4 4 9 e
>>> df.replace({{'A': 0, 'B': 5}}, 100)
A B C
0 100 100 a
1 1 6 b
2 2 7 c
3 3 8 d
4 4 9 e
>>> df.replace({{'A': {{0: 100, 4: 400}}}})
A B C
0 100 5 a
1 1 6 b
2 2 7 c
3 3 8 d
4 400 9 e
**Regular expression `to_replace`**
>>> df = pd.DataFrame({{'A': ['bat', 'foo', 'bait'],
... 'B': ['abc', 'bar', 'xyz']}})
>>> df.replace(to_replace=r'^ba.$', value='new', regex=True)
A B
0 new abc
1 foo new
2 bait xyz
>>> df.replace({{'A': r'^ba.$'}}, {{'A': 'new'}}, regex=True)
A B
0 new abc
1 foo bar
2 bait xyz
>>> df.replace(regex=r'^ba.$', value='new')
A B
0 new abc
1 foo new
2 bait xyz
>>> df.replace(regex={{r'^ba.$': 'new', 'foo': 'xyz'}})
A B
0 new abc
1 xyz new
2 bait xyz
>>> df.replace(regex=[r'^ba.$', 'foo'], value='new')
A B
0 new abc
1 new new
2 bait xyz
Compare the behavior of ``s.replace({{'a': None}})`` and
``s.replace('a', None)`` to understand the peculiarities
of the `to_replace` parameter:
>>> s = pd.Series([10, 'a', 'a', 'b', 'a'])
When one uses a dict as the `to_replace` value, it is like the
value(s) in the dict are equal to the `value` parameter.
``s.replace({{'a': None}})`` is equivalent to
``s.replace(to_replace={{'a': None}}, value=None, method=None)``:
>>> s.replace({{'a': None}})
0 10
1 None
2 None
3 b
4 None
dtype: object
When ``value`` is not explicitly passed and `to_replace` is a scalar, list
or tuple, `replace` uses the method parameter (default 'pad') to do the
replacement. So this is why the 'a' values are being replaced by 10
in rows 1 and 2 and 'b' in row 4 in this case.
>>> s.replace('a')
0 10
1 10
2 10
3 b
4 b
dtype: object
On the other hand, if ``None`` is explicitly passed for ``value``, it will
be respected:
>>> s.replace('a', None)
0 10
1 None
2 None
3 b
4 None
dtype: object
.. versionchanged:: 1.4.0
Previously the explicit ``None`` was silently ignored.
"""
_shared_docs[
"idxmin"
] = """
Return index of first occurrence of minimum over requested axis.
NA/null values are excluded.
Parameters
----------
axis : {{0 or 'index', 1 or 'columns'}}, default 0
The axis to use. 0 or 'index' for row-wise, 1 or 'columns' for column-wise.
skipna : bool, default True
Exclude NA/null values. If an entire row/column is NA, the result
will be NA.
numeric_only : bool, default {numeric_only_default}
Include only `float`, `int` or `boolean` data.
.. versionadded:: 1.5.0
Returns
-------
Series
Indexes of minima along the specified axis.
Raises
------
ValueError
* If the row/column is empty
See Also
--------
Series.idxmin : Return index of the minimum element.
Notes
-----
This method is the DataFrame version of ``ndarray.argmin``.
Examples
--------
Consider a dataset containing food consumption in Argentina.
>>> df = pd.DataFrame({{'consumption': [10.51, 103.11, 55.48],
... 'co2_emissions': [37.2, 19.66, 1712]}},
... index=['Pork', 'Wheat Products', 'Beef'])
>>> df
consumption co2_emissions
Pork 10.51 37.20
Wheat Products 103.11 19.66
Beef 55.48 1712.00
By default, it returns the index for the minimum value in each column.
>>> df.idxmin()
consumption Pork
co2_emissions Wheat Products
dtype: object
To return the index for the minimum value in each row, use ``axis="columns"``.
>>> df.idxmin(axis="columns")
Pork consumption
Wheat Products co2_emissions
Beef consumption
dtype: object
"""
_shared_docs[
"idxmax"
] = """
Return index of first occurrence of maximum over requested axis.
NA/null values are excluded.
Parameters
----------
axis : {{0 or 'index', 1 or 'columns'}}, default 0
The axis to use. 0 or 'index' for row-wise, 1 or 'columns' for column-wise.
skipna : bool, default True
Exclude NA/null values. If an entire row/column is NA, the result
will be NA.
numeric_only : bool, default {numeric_only_default}
Include only `float`, `int` or `boolean` data.
.. versionadded:: 1.5.0
Returns
-------
Series
Indexes of maxima along the specified axis.
Raises
------
ValueError
* If the row/column is empty
See Also
--------
Series.idxmax : Return index of the maximum element.
Notes
-----
This method is the DataFrame version of ``ndarray.argmax``.
Examples
--------
Consider a dataset containing food consumption in Argentina.
>>> df = pd.DataFrame({{'consumption': [10.51, 103.11, 55.48],
... 'co2_emissions': [37.2, 19.66, 1712]}},
... index=['Pork', 'Wheat Products', 'Beef'])
>>> df
consumption co2_emissions
Pork 10.51 37.20
Wheat Products 103.11 19.66
Beef 55.48 1712.00
By default, it returns the index for the maximum value in each column.
>>> df.idxmax()
consumption Wheat Products
co2_emissions Beef
dtype: object
To return the index for the maximum value in each row, use ``axis="columns"``.
>>> df.idxmax(axis="columns")
Pork co2_emissions
Wheat Products consumption
Beef co2_emissions
dtype: object
"""