使用 iloc 在 pandas dataframe 中选择值时保持浮点精度

Question

My code:

import pandas as pd 

pd.set_option('display.float_format','{:.2f}'.format)

df = pd.Series([500.0, 200.0, 300.0])
df
0   500.00
1   200.00
2   300.00
dtype: float64

df.iloc[1]
200.0

I want df.iloc[1] to return 200.00, can anyone explain what's happening here and how to get the desired result please.

Answer 1

Indexing the way you did will return the actual value at that index, which is type float.

type(df.iloc[1]) # returns 'numpy.float64'

What you would like to do is print the entire row, like so:

df.iloc[[1]]

In this case, the index returns a series:

type(df.iloc[[1]]) # returns 'pandas.core.series.Series'