Pandas style.set_precision not working as expected

[Peter9192]

I expected the following code to give me a representation of my data that is rounded or truncated to 2 decimals.

import pandas as pd
import numpy as np

df = pd.DataFrame(data = np.random.randn(4,4), columns=['A','B','C','D'])
df.style.set_precision(2)

However, it will always return 2 digits instead, so for example, I want 2.37419 to be displayed as 2.37, but instead this code will give me 2.4. Am I overseeing something or is this a bug?

Note that the following code works as I expected, but then I change a general setting whereas I would like to apply it only to the current output:

pd.set_option('display.precision',2)
df

I'm using pandas version 0.18.1 in Jupyter notebook on Firefox, with python 2.7.11.final.0 and IPython 4.1.2 on 64-bits linux.

[TomAugspurger]

I believe this is just reusing something like this from python

>>> '{:.2g}'.format(2.37419)
'2.4'

Would take a PR fixing this to have the 2.37 like expected. I think we recently fixed a similar problem with the 'display.precision' option.

[ruchigarg-DS]

df = pd.DataFrame([123.4567, 234.5678, 345.6789, 456.7890],
index=['a','b','c','d'],
columns=['cost'])
df.style.set_precision(precision=2)

	cost
1.2e+02
2.3e+02
3.5e+02
4.6e+02

	cost
1.2e+02
2.3e+02
3.5e+02
4.6e+02