Data frame column with conditional data - 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?

joris · Accepted Answer · 2012-11-10 23:07:08Z

4

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

answered Nov 10, 2012 at 23:07

joris

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