Evaluating multiple conditions in if-then-else block in a Pandas DataFrame

Question

I want to create a new column in a Pandas DataFrame by evaluating multiple conditions in an if-then-else block.

if events.hour <= 6:
    events[\'time_slice\         


        

Answer 1

Here's a NumPy approach to it -

tags = ['night','morning','afternoon','evening']
events['time_slice'] = np.take(tags,((events.hour.values-1)//6).clip(min=0))

Sample run -

In [130]: events
Out[130]: 
   hour time_slice
0     0      night
1     8    morning
2    16  afternoon
3    20    evening
4     2      night
5    14  afternoon
6     7    morning
7    18  afternoon
8     8    morning
9    22    evening