Pandas shows SettingWithCopyWarning after train_test_split [duplicate]

Answer 1

You can workaround it as follows:

In [16]: Xt = Xt.copy()

In [17]: Xt.iloc[0,0]=6

In [18]: Xt
Out[18]:
   A  B
0  6  2
2  7  3
1  5  5

In [19]: X
Out[19]:
   A   B
0  2   2     # <--- NOTE: the value in the original DF has NOT been changed
1  5   5
2  7   3
3  8  51
4  9   5

Alternatively you can use numpy.split(...) method