Slicing a Pandas DataFrame into a new DataFrame

Question

I would like to slice a DataFrame with a Boolean index obtaining a copy, and then do stuff on that copy independently of the original DataFrame.

Judging from this a

Answer 1

You need copy with boolean indexing, new DataFrame constructor is not necessary:

d2 = d1[d1.a > 1].copy()

Explanation of warning:

If you modify values in d2 later you will find that the modifications do not propagate back to the original data (d1), and that Pandas does warning.