docs: add code samples for index and column properties (#212)

Thank you for opening a Pull Request! Before submitting your PR, there are a few things you can do to make sure it goes smoothly: - [ ] Make sure to open an issue as a [bug/issue](https://togithub.com/googleapis/python-bigquery-dataframes/issues/new/choose) before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea - [ ] Ensure the tests and linter pass - [ ] Code coverage does not decrease (if any source code was changed) - [x] Appropriate docs were updated - `DataFrame.columns`: https://screenshot.googleplex.com/3Bwdb482FBfEsi2 - `DataFrame.index`: https://screenshot.googleplex.com/4iJymH3FxMn8Hhb - `Series.index`: https://screenshot.googleplex.com/7MXQcuASbQ3c8s5 Fixes internal issue 310260952 🦕

Author: shobsi

third_party/bigframes_vendored/pandas/core/frame.py

@@ -3106,14 +3106,91 @@ def index(self):
  index is used for label-based access and alignment, and can be accessed
  or modified using this attribute.
 
+ **Examples:**
+
+ >>> import bigframes.pandas as bpd
+ >>> bpd.options.display.progress_bar = None
+
+ You can access the index of a DataFrame via ``index`` property.
+
+ >>> df = bpd.DataFrame({'Name': ['Alice', 'Bob', 'Aritra'],
+ ... 'Age': [25, 30, 35],
+ ... 'Location': ['Seattle', 'New York', 'Kona']},
+ ... index=([10, 20, 30]))
+ >>> df
+ Name Age Location
+ 10 Alice 25 Seattle
+ 20 Bob 30 New York
+ 30 Aritra 35 Kona
+ <BLANKLINE>
+ [3 rows x 3 columns]
+ >>> df.index # doctest: +ELLIPSIS
+ <bigframes.core.indexes.index.Index object at ...>
+ >>> df.index.values
+ array([10, 20, 30], dtype=object)
+
+ Let's try setting a new index for the dataframe and see that reflect via
+ ``index`` property.
+
+ >>> df1 = df.set_index(["Name", "Location"])
+ >>> df1
+ Age
+ Name Location
+ Alice Seattle 25
+ Bob New York 30
+ Aritra Kona 35
+ <BLANKLINE>
+ [3 rows x 1 columns]
+ >>> df1.index # doctest: +ELLIPSIS
+ <bigframes.core.indexes.index.Index object at ...>
+ >>> df1.index.values
+ array([('Alice', 'Seattle'), ('Bob', 'New York'), ('Aritra', 'Kona')],
+ dtype=object)
+
  Returns:
  The index labels of the DataFrame.
  """
  raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
  @property
  def columns(self):
- "The column labels of the DataFrame."
+ """The column labels of the DataFrame.
+
+ **Examples:**
+
+ >>> import bigframes.pandas as bpd
+ >>> bpd.options.display.progress_bar = None
+
+ You can access the column labels of a DataFrame via ``columns`` property.
+
+ >>> df = bpd.DataFrame({'Name': ['Alice', 'Bob', 'Aritra'],
+ ... 'Age': [25, 30, 35],
+ ... 'Location': ['Seattle', 'New York', 'Kona']},
+ ... index=([10, 20, 30]))
+ >>> df
+ Name Age Location
+ 10 Alice 25 Seattle
+ 20 Bob 30 New York
+ 30 Aritra 35 Kona
+ <BLANKLINE>
+ [3 rows x 3 columns]
+ >>> df.columns
+ Index(['Name', 'Age', 'Location'], dtype='object')
+
+ You can also set new labels for columns.
+
+ >>> df.columns = ["NewName", "NewAge", "NewLocation"]
+ >>> df
+ NewName NewAge NewLocation
+ 10 Alice 25 Seattle
+ 20 Bob 30 New York
+ 30 Aritra 35 Kona
+ <BLANKLINE>
+ [3 rows x 3 columns]
+ >>> df.columns
+ Index(['NewName', 'NewAge', 'NewLocation'], dtype='object')
+
+ """
  raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
  def value_counts(

third_party/bigframes_vendored/pandas/core/series.py

@@ -44,7 +44,54 @@ def struct(self):
 
  @property
  def index(self):
- """The index (axis labels) of the Series."""
+ """The index (axis labels) of the Series.
+
+ The index of a Series is used to label and identify each element of the
+ underlying data. The index can be thought of as an immutable ordered set
+ (technically a multi-set, as it may contain duplicate labels), and is
+ used to index and align data.
+
+ **Examples:**
+
+ >>> import bigframes.pandas as bpd
+ >>> bpd.options.display.progress_bar = None
+
+ You can access the index of a Series via ``index`` property.
+
+ >>> df = bpd.DataFrame({'Name': ['Alice', 'Bob', 'Aritra'],
+ ... 'Age': [25, 30, 35],
+ ... 'Location': ['Seattle', 'New York', 'Kona']},
+ ... index=([10, 20, 30]))
+ >>> s = df["Age"]
+ >>> s
+ 10 25
+ 20 30
+ 30 35
+ Name: Age, dtype: Int64
+ >>> s.index # doctest: +ELLIPSIS
+ <bigframes.core.indexes.index.Index object at ...>
+ >>> s.index.values
+ array([10, 20, 30], dtype=object)
+
+ Let's try setting a multi-index case reflect via ``index`` property.
+
+ >>> df1 = df.set_index(["Name", "Location"])
+ >>> s1 = df1["Age"]
+ >>> s1
+ Name Location
+ Alice Seattle 25
+ Bob New York 30
+ Aritra Kona 35
+ Name: Age, dtype: Int64
+ >>> s1.index # doctest: +ELLIPSIS
+ <bigframes.core.indexes.index.Index object at ...>
+ >>> s1.index.values
+ array([('Alice', 'Seattle'), ('Bob', 'New York'), ('Aritra', 'Kona')],
+ dtype=object)
+
+ Returns:
+ The index labels of the Series.
+ """
  raise NotImplementedError(constants.ABSTRACT_METHOD_ERROR_MESSAGE)
 
  @property