How to group various groups in python into one-CodePudding

I have a dataset which I want to group by the age. So, here is the first part of the dataset:

It is a simulation for a inventory data. Größe means the number of people with the age (Alter) 15. Risiko gives every person a number and Geschlecht is feminine or masculine.

I want to add a column "Group" and give every people, which have the age 15-19 one number, than with age 20-24 one number and so on. How can I do this?

CodePudding user response：

You can use map and lambda to create a new column like so :

def return_age_from_range(age):
    # Max value in range is excluded, so remember to add  1 to the range you want
    if age in range(15, 20):
       return 1
    elif age in range(20, 25):
       return 2
    # and so on...

df['group'] = df.alter.map(lambda x: return_age_from_range(x))

CodePudding user response：

Use numpy.select:

In [488]: import numpy as np

In [489]: conds = [df['Alter'].between(15,19), df['Alter'].between(20,24), df['Alter'].between(24,28)]

In [490]: choices = [1,2,3]

In [493]: df['Group'] = np.select(conds, choices)

In [494]: df
Out[494]: 
   Größe  Risiko Geschlecht  Alter  Group
0     95       1          F     15      1
1     95       2          F     15      1
2     95       3          M     15      1
3     95       4          F     15      1
4     95       5          M     15      1
5     95       6          M     15      1
6     95       7          M     15      1
7     95       8          F     15      1
8     95       9          M     15      1