使用 for 循环
创建熊猫列
原文:https://www.geesforgeks.org/create-a-pandas-column-use-for-loop/
让我们看看如何使用 for 循环在 pandas dataframe 中创建一个列。当我们需要处理之前为此目的创建的数据帧的数据时，有时需要这样的操作，我们需要这种类型的计算，这样我们就可以处理现有的数据，并创建一个单独的列来存储数据。
这可以通过 for-loop 轻松完成。列的数据可以从现有的数据框或任何数组中获取。
# importing libraries
import pandas as pd
import numpy as np
raw_Data = {'Voter_name': ['Geek1', 'Geek2', 'Geek3', 'Geek4',
'Geek5', 'Geek6', 'Geek7', 'Geek8'],
'Voter_age': [15, 23, 25, 9, 67, 54, 42, np.NaN]}
df = pd.DataFrame(raw_Data, columns = ['Voter_name', 'Voter_age'])
# //DataFrame will look like
#
# Voter_name Voter_age
# Geek1 15
# Geek2 23
# Geek3 25
# Geek4 09
# Geek5 67
# Geek6 54
# Geek7 42
# Geek8 not a number
eligible = []
# For each row in the column
for age in df['Voter_age']:
if age >= 18: # if Voter eligible
eligible.append('Yes')
elif age < 18: # if voter is not eligible
eligible.append("No")
else:
eligible.append("Not Sure")
# Create a column from the list
df['Voter'] = eligible
print(df)
Output:
Voter_name Voter_age Voter
0 Geek1 15 No
1 Geek2 23 Yes
2 Geek3 25 Yes
3 Geek4 9 No
4 Geek5 67 Yes
5 Geek6 54 Yes
6 Geek7 42 Yes
7 Geek8 NaN Not Sure
