Question

我想在以下语句为真的“分数”列的每一行中添加“ 1”

import pandas as pd
import numpy as np


df = pd.read_csv(Path1 + 'Test.csv')
df.replace(np.nan, 0, inplace=True)
df[(df.Day7 >= 500)]

Sample Value

Output

Answer 1

您在那儿。只需使用df.loc[mask, "Score"] = 1：

import numpy as np
import pandas as pd

df = pd.DataFrame({"Day7":np.random.rand(5)*1000,
                   "Score": np.random.rand(5)})
print(df)
df.loc[(df.Day7>=500), "Score"] = 1
print(df)

Answer 2

请您尝试以下。

df['score']=np.where(df['Day7']>=500,1,"")

或根据OP的评论（在此处添加@ anky_91的增强型解决方案）：

np.where((df['Day7']>=500)&(df['Day7']<1000),1,"")

当我们打印df时，将输出以下内容。

    Cat          Day7    score
0   Advertisir   145    
1   Blogs        56 
2   Business     92 
3   Classfied    23 
4   Continuin    110    
5   Corporate    1974     1

Answer 3

df = df.assign(Score=0)
df.Score = df.Day7 >= 500

如果条件匹配，如何增加价值，Python

3 个答案: