使用 apply 和 map 在 Pandas 中添加两列的值
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add the values of two columns in pandas using apply and map
提问by Shiva Krishna Bavandla
Basically i was trying to add two columns data and reflect it on another column and the data was below
基本上我试图添加两列数据并将其反映在另一列上，数据在下面
data = {'name': ['Jason', 'Molly', 'Tina', 'Jake', 'Amy'],
'year': [2012, 2012, 2013, 2014, 2014],
'reports': [4, 24, 31, 2, 3],
'coverage': [25, 94, 57, 62, 70]}
df = pd.DataFrame(data, index = ['Cochice', 'Pima', 'Santa Cruz', 'Maricopa', 'Yuma'])
df
coverage name reports year
Cochice 25 Jason 4 2012
Pima 94 Molly 24 2012
Santa Cruz 57 Tina 31 2013
Maricopa 62 Jake 2 2014
Yuma 70 Amy 3 2014
I am using above data frame for testing and I want to add the data of two columns coverageand reportsand replace it with one column as below
我使用的数据帧以上的测试，我想补充两列的数据coverage，并reports与一列如下更换
df[["coverage"]] = df[["coverage"]].apply(lambda value:add(df["coverage"], df["reports"]))
and my result should be
我的结果应该是
coverage name reports year
Cochice 25+4=29 Jason 4 2012
Pima 94+24 Molly 24 2012
Santa Cruz 57+31 Tina 31 2013
Maricopa 62+2 Jake 2 2014
Yuma 70+3 Amy 3 2014
But it was not working, can anyone please let me know what's wrong in the above code ?
但它不起作用，任何人都可以让我知道上面的代码有什么问题吗？
Edit
编辑
My add function
我的添加功能
def add(one, two):
return one + two
回答by jezrael
You need simply add:
你只需要add：
df["coverage"] = df["coverage"].add(df["reports"])
print (df)
coverage name reports year
Cochice 29 Jason 4 2012
Pima 118 Molly 24 2012
Santa Cruz 88 Tina 31 2013
Maricopa 64 Jake 2 2014
Yuma 73 Amy 3 2014
Or:
或者：
df["coverage"] = df["coverage"] + df["reports"]
print (df)
coverage name reports year
Cochice 29 Jason 4 2012
Pima 118 Molly 24 2012
Santa Cruz 88 Tina 31 2013
Maricopa 64 Jake 2 2014
Yuma 73 Amy 3 2014
Your code need axis=1:
您的代码需要axis=1：
def add(one, two):
return one + two
df["coverage"] = df.apply(lambda x :add(x["coverage"], x["reports"]), axis=1)
print (df)
coverage name reports year
Cochice 29 Jason 4 2012
Pima 118 Molly 24 2012
Santa Cruz 88 Tina 31 2013
Maricopa 64 Jake 2 2014
Yuma 73 Amy 3 2014
