Inconsistent plotting of DateTimeIndex

[gliptak]

Code Sample, a copy-pastable example if possible

%matplotlib inline
import seaborn
import pandas as pd
import numpy as np
dates = pd.date_range('2016-01-01', '2016-12-31', freq='D')
s = pd.Series(np.random.uniform(size=366), index=dates)

s.plot(kind='line')

s.plot(kind='bar')

Problem description

line and bar displays dates differently as per screenshots attached.

Expected Output

Both line and bar displaying dates the same (preferably the readable layout)

Output of pd.show_versions()

INSTALLED VERSIONS ------------------ commit: None python: 2.7.12.final.0 python-bits: 64 OS: Linux OS-release: 4.10.0-26-generic machine: x86_64 processor: x86_64 byteorder: little LC_ALL: None LANG: en_US.UTF-8 LOCALE: None.None

pandas: 0.20.3
pytest: 3.1.2
pip: 9.0.1
setuptools: 36.0.1
Cython: None
numpy: 1.13.1
scipy: 0.19.0
xarray: None
IPython: 5.4.1
sphinx: None
patsy: 0.4.1
dateutil: 2.6.1
pytz: 2017.2
blosc: None
bottleneck: None
tables: None
numexpr: None
feather: None
matplotlib: 2.0.2
openpyxl: None
xlrd: 1.0.0
xlwt: None
xlsxwriter: None
lxml: None
bs4: 4.6.0
html5lib: 0.999999999
sqlalchemy: None
pymysql: None
psycopg2: None
jinja2: 2.9.6
s3fs: None
pandas_gbq: None
pandas_datareader: 0.5.0

[gfyoung]

It seems like your issue is primarily with .bar. I think I've run into this issue before too...though I think it just matplotlib funkiness

cc @TomAugspurger

[TomAugspurger]

Barplot makes one label per bar. If you want something else then you're probably best off doing the ticks manually.

[gfyoung]

Barplot makes one label per bar. If you want something else then you're probably best off doing the ticks manually.

Hmmm...okay. Could we add that to the documentation to clarify (at least to differentiate between line plot so as to avoid this confusion again)?

[gliptak]

pandas.Series.plot() offers an abstraction over matplotlib (with different parameters). Could the default be changed (instead of explaining why it looks that way in the documentation)? Thanks

[gfyoung]

@gliptak : API changes are generally a little trickier to do because people may be relying on our current defaults. That being said, feel free to put a PR together with the proposed changes. Documentation improvements at the very least would be great here.