python - Extract a column from a DataFrame -

just basic question block me lot. how can extract column dataframe , have dataframe output ?

suppose have :

>>> dfm <class 'pandas.core.frame.dataframe'> datetimeindex: 17544 entries, 2015-01-01 00:00:00 2016-12-31 23:00:00 data columns (total 23 columns): t1       17544  non-null values t2       17544  non-null values  >>> df = dfm['t1'] 

here df not dataframe. found subterfuge copy dataframe , del columns it's time consumming.

alexis

you can use [[]] instead of []:

df = dfm[['t1']] 

for example:

from pandas import dataframe df = dataframe(dict(a=range(10), b=range(10)))  type(df['b']) # <class 'pandas.core.series.series'> type(df[['b']]) # <class 'pandas.core.frame.dataframe'> 

this works because passing list of 1 (['b']) column subset operator.