Code Sample, a copy-pastable example if possible


>>> import pandas as pd
>>> a = pd.Series(range(10))
>>> a.sort_index(kind='mergesort')

Problem description

The documentation present the 'kind' optional argument: http://pandas.pydata.org/pandas-docs/stable/generated/pandas.Series.sort_index.html#pandas.Series.sort_index

But it is not implemented (while it is for depreciated sort() )

Output of pd.show_versions()

# Paste the output here pd.show_versions() here INSTALLED VERSIONS ------------------ commit: None python: 2.7.9.final.0 python-bits: 64 OS: Linux OS-release: 3.16.0-4-amd64 machine: x86_64 processor: byteorder: little LC_ALL: None LANG: fr_FR.utf8 LOCALE: fr_FR.UTF-8 pandas: 0.19.0 nose: 1.3.4 pip: 1.5.6 setuptools: 5.5.1 Cython: 0.21.1 numpy: 1.8.2 scipy: 0.14.0 statsmodels: 0.6.1 xarray: None IPython: 5.1.0 sphinx: None patsy: 0.4.1 dateutil: 2.2 pytz: 2012c blosc: None bottleneck: None tables: None numexpr: None matplotlib: 1.4.2 openpyxl: None xlrd: None xlwt: None xlsxwriter: None lxml: None bs4: 4.4.0 html5lib: 0.999 httplib2: 0.9.1 apiclient: None sqlalchemy: None pymysql: None psycopg2: None jinja2: 2.7.3 boto: 2.38.0 pandas_datareader: None

Comment From: jreback

this is a dupe of #13859 and fixed in https://github.com/pandas-dev/pandas/pull/14445 (its in 0.20.0)

Comment From: pelodelfuego

Ty for your quick reply and moreover your awesome work !