如何在 groupby python 数据框中找到最大值

Question

这是我table的问题。

我想得到一个有 3 条线的图形。

（图例：aaa_bbb_L、aaa_bbb_Q、aaa_bbb_ZL）

df = pd.DataFrame({ 
'A': ['aaa','aaa','aaa','aaa','aaa','aaa','aaa','aaa','aaa','aaa','aaa','aaa'],
'B': ['bbb','bbb','bbb','bbb','bbb','bbb','bbb','bbb','bbb','bbb','bbb','bbb'],
'DC': ['L','L','L','L','Q','Q','Q','Q','ZL','ZL','ZL','ZL'],
'score' : [0.1,0.2,0.3,0.4,0.11,0.21,0.31,0.39,0.1,0.22,0.3,0.42],
'max_sel' : [2.0,3.3,6.0,7.1,3.1,4.0,8.0,8.9,1.2,3.0,5.0,6.6]
})

df.groupby(["A","B","DC"]).plot(legend = True, xlabel='score', ylabel="max_sel",x="score", y = "max_sel")
plt.show()

我试过了，但是上面的代码做了 3 个不同的图形。如何得到这样的数字

I want to get this

Answer 1

这是你想要的吗？

fig, ax = plt.subplots()
for key, grp in df.groupby(['A','B','DC']):
        ax = grp.plot(ax=ax, kind='line', x='score', y='max_sel', label=key, marker='o')

给出以下结果：

如何在 groupby python 数据框中找到最大值

how to find max value in groupby python dataframe

python

matplotlib

pandas-groupby