我有一只DataFrame像熊猫一样的熊猫.
df = pd.DataFrame({'id' : [1,1,1,2,2,3,3,3,3,4,4,5,6,6,6,7,7],
'value' : ["first","second","second","first",
"second","first","third","fourth",
"fifth","second","fifth","first",
"first","second","third","fourth","fifth"]})
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我想通过["id","value"]对此进行分组,并得到每个组的第一行.
id value
0 1 first
1 1 second
2 1 second
3 2 first
4 2 second
5 3 first
6 3 third
7 3 fourth
8 3 fifth
9 4 second
10 4 fifth
11 5 first
12 6 first
13 6 second
14 6 third
15 7 fourth
16 7 fifth
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预期结果
id value
1 first
2 first
3 first
4 second
5 …Run Code Online (Sandbox Code Playgroud)