Issue 1:
Hello,

I did

import numpy as np
import pandas as pd
from matplotlib.pyplot as plt

idx = pd.date_range('20140101', '20140201')
df = pd.DataFrame(index=idx)
df['col0'] = np.random.randn(len(idx))
s_idx = pd.Series(idx, index=idx) # need to do this because we can't shift index
diff_idx = (s_idx-s_idx.shift(1)).fillna(pd.Timedelta(0))
df['diff_dt'] = diff_idx
df['diff_dt'].plot()

but it raises Empty 'Series': no numeric data to plot

In [78]: df.dtypes
Out[78]:
col0 float64
diff_dt timedelta64[ns]
dtype: object

In [79]: type(df['diff_dt'][1])
Out[79]: pandas.tslib.Timedelta

I don't understand if data inside diff_dt columns are numpy.timedelta64 or pd.Timedelta

df['diff_dt'].map(lambda x: x.value)

raises AttributeError: 'numpy.timedelta64' object has no attribute 'value'

but it seems that I can get valuefor a given data (let's say row 10)

In [97]: df['diff_dt'][10].value
Out[97]: 86400000000000

I don't understand why...

But I also don't understand how I could plot diff_dt column without doing an uggly:

df['diff_dt'].map(lambda x: x/np.timedelta64(1, 'ns')).plot()

But I don't know how I could automatically get this np.timedelta64(1, 'ns')

Maybe Pandas could plot Timedelta (or np.timedelta64) out of the box ?

because that's interesting to know for example if sampling period is constant.

Kind regards

Issue 2:
Code Sample

import pandas as pd
from pandas.compat import StringIO
import matplotlib.pyplot as plt

dat = """c1,c2,c3
1000,2000,1500
9000,8000,1600"""

df = pd.read_csv(StringIO(dat))

print(df)

df.plot.bar()
plt.show()

df = df.apply(lambda x: pd.to_timedelta(x, unit='ms'))

print(df)

df.plot.bar()
plt.show()

Problem description

plot.bar() works with numerical values (int, float).

c1 c2 c3
0 1000 2000 1500
1 9000 8000 1600

not with Timedelta

c1 c2 c3
0 00:00:01 00:00:02 00:00:01.500000
1 00:00:09 00:00:08 00:00:01.600000

df.plot.bar()
File "/Users/scls/anaconda/lib/python3.6/site-packages/pandas/plotting/_core.py", line 2659, in bar
return self(kind='bar', x=x, y=y, **kwds)
File "/Users/scls/anaconda/lib/python3.6/site-packages/pandas/plotting/_core.py", line 2620, in __call__
sort_columns=sort_columns, **kwds)
File "/Users/scls/anaconda/lib/python3.6/site-packages/pandas/plotting/_core.py", line 1857, in plot_frame
**kwds)
File "/Users/scls/anaconda/lib/python3.6/site-packages/pandas/plotting/_core.py", line 1682, in _plot
plot_obj.generate()
File "/Users/scls/anaconda/lib/python3.6/site-packages/pandas/plotting/_core.py", line 236, in generate
self._compute_plot_data()
File "/Users/scls/anaconda/lib/python3.6/site-packages/pandas/plotting/_core.py", line 345, in _compute_plot_data
'plot'.format(numeric_data.__class__.__name__))
TypeError: Empty 'DataFrame': no numeric data to plot

Expected Output

Timedelta on y axis should be displayed

Output of pd.show_versions()

/Users/scls/anaconda/lib/python3.6/site-packages/xarray/core/formatting.py:16: FutureWarning: The pandas.tslib module is deprecated and will be removed in a future version.
from pandas.tslib import OutOfBoundsDatetime

INSTALLED VERSIONS

commit: None

python: 3.6.1.final.0

python-bits: 64

OS: Darwin

OS-release: 16.6.0

machine: x86_64

processor: i386

byteorder: little

LC_ALL: None

LANG: fr_FR.UTF-8

LOCALE: fr_FR.UTF-8

pandas: 0.20.1

pytest: 3.1.2

pip: 9.0.1

setuptools: 27.2.0

Cython: 0.25.2

numpy: 1.12.1

scipy: 0.19.0

xarray: 0.9.5

IPython: 5.3.0

sphinx: 1.5.6

patsy: 0.4.1

dateutil: 2.6.0

pytz: 2017.2

blosc: None

bottleneck: 1.2.1

tables: 3.3.0

numexpr: 2.6.2

feather: None

matplotlib: 2.0.2

openpyxl: 2.4.7

xlrd: 1.0.0

xlwt: 1.2.0

xlsxwriter: 0.9.6

lxml: 3.7.3

bs4: 4.6.0

html5lib: 0.999

sqlalchemy: 1.1.9

pymysql: None

psycopg2: None

jinja2: 2.9.6

s3fs: None

pandas_gbq: None

pandas_datareader: 0.4.0