带有条件数据的数据框列-Python

Question

I have some percentages in a data frame column

pc
0.32
0.45
0.49
0.60
0.68
0.87

And i want to end up with something like this

pc     group
0.32    1
0.45    2
0.49    2
0.60    2
0.68    3
0.87    3

I've tried

df["group"]=3

if df["pc"]<0.66:
    df["group"]=2

elif df["pc"]<0.33:
    df["group"]=1

but all i get is

ValueError: The truth value of an array with more than one element is ambiguous.

Any ideas?

Answer 1

df["group"][df["pc"] < 0.66] = 2
df["group"][df["pc"] < 0.33] = 1