Python pandas: how to change categorical values in between 2 different categories

Question

Hi everyone I am working on stock market data and I was wondering how to change the pandas data frame as below

From: Signal	To: Signal_new
Buy	Buy
Buy	Hold
Buy	Hold
Sell	Sell
Sell	Hold
Sell	Hold
Sell	Hold
Buy	Buy

thanks in advance!

Answer 1

Try this:

df[df['Signal'] == df['Signal'].shift(1)] = 'Hold'

Output:

>>> df
  Signal
0    Buy
1   Hold
2   Hold
3   Sell
4   Hold
5   Hold
6   Hold
7    Buy