Pandas Signature of get_level_values not as documented

import numpy as np 
import pandas as pd

data = pd.DataFrame(np.arange(8).reshape(2,4)).set_index([0,1])

print(type(data.index.get_level_values(0)))

returns

while docs say it should return an ndarray.

The actual behaviour is probably useful and the documented behaviour can be obtained by for example: data.index.get_level_values(0).values so the situation could be improved by updating the docstring but I think the name could be better.

version info:

INSTALLED VERSIONS

commit: None python: 3.6.0.final.0 python-bits: 64 OS: Linux OS-release: 4.8.0-42-generic machine: x86_64 processor: x86_64 byteorder: little LC_ALL: None LANG: en_GB.UTF-8 LOCALE: en_GB.UTF-8

pandas: 0.19.2 nose: 1.3.7 pip: 9.0.1 setuptools: 27.2.0 Cython: 0.25.2 numpy: 1.11.3 scipy: 0.18.1 statsmodels: 0.6.1 xarray: 0.9.1 IPython: 5.1.0 sphinx: 1.5.1 patsy: 0.4.1 dateutil: 2.6.0 pytz: 2016.10 blosc: None bottleneck: 1.2.0 tables: 3.3.0 numexpr: 2.6.1 matplotlib: 2.0.0 openpyxl: 2.4.1 xlrd: 1.0.0 xlwt: 1.2.0 xlsxwriter: 0.9.6 lxml: 3.7.2 bs4: 4.5.3 html5lib: 0.999 httplib2: None apiclient: None sqlalchemy: 1.1.5 pymysql: None psycopg2: None jinja2: 2.9.4 boto: 2.45.0 pandas_datareader: None

Comment From: chris-b1

Thanks for the report - this is corrected on master, was fixed as part of #15245

In [36]: pd.__version__
Out[36]: '0.19.0+566.g54e71a7'

In [37]: data.index.get_level_values?
Signature: data.index.get_level_values(level)
Docstring:
Return vector of label values for requested level,
equal to the length of the index

Parameters
----------
level : int or level name

Returns
-------
values : Index