熔融熊猫数据帧和分割两行基于

Question

柱

我有以下形式的数据帧：

    0 
college  gender 
Engineering F  117 
      M  2240 

，我想将它更改为：

college  M:F 
Engineering 19:1 

其中M：F代表的比率男性与女性。

有没有办法用熊猫做到这一点，而无需遍历所有行？

Answer 1

看来你需要unstack重塑，然后划分：

df = df.unstack()[0] 
#same as 
#df = df[0].unstack() 

df['M:F'] = df['M']/df['F'] 
#same as 
#df['M:F'] = df['M'].div(df['F']) 

---

print (df) 
         0 
college  gender  
Engineering F  117 
      M  2240 
Engineering1 F  117 
      M  2240 

df = df.unstack()[0] 
df['M:F'] = df['M'].div(df['F']) 
print (df) 
gender   F  M  M:F 
college       
Engineering 117 2240 19.145299 
Engineering1 117 2240 19.145299 

print (df[['M:F']]) 
gender    M:F 
college     
Engineering 19.145299 
Engineering1 19.145299