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Python 数据帧条件Groupby_Python_Pandas_Pandas Groupby - Fatal编程技术网

Python 数据帧条件Groupby

Python 数据帧条件Groupby,python,pandas,pandas-groupby,Python,Pandas,Pandas Groupby,我有这个DF: df = pd.DataFrame(data=[[-2.000000, -1.958010, 0.2], [-1.958010, -1.916030, 0.4], [-1.916030, -1.874040, 0.3], [-1.874040, -1.832050, 0.6], [-1.832050, -1.79007

我有这个DF:

df = pd.DataFrame(data=[[-2.000000, -1.958010,  0.2],
                   [-1.958010, -1.916030,  0.4],
                   [-1.916030, -1.874040,  0.3],  
                   [-1.874040, -1.832050,  0.6],
                   [-1.832050, -1.790070, 0.8],
                   [-1.790070, -1.748080,  0.2]],columns=['egystart','egyend','fx'])
所以我想每两行分组,得到fx作为这两行的平均值。egystart应该由第一排的egystart和egyend组成,egyend应该由第二排的egyend组成

在这种情况下,我应获得:

-2.000000 -1.916030  0.3
-1.916030 -1.832050  0.45  
-1.832050 -1.748080  0.5
所以我试过这样的方法:

df.groupby((df.egystart == df.egyend.shift(1)).cumsum()).agg({'egystart':min, 'egyend':max, 'fx':HERE_THE_MEAN_VALUE})

但它不起作用

您可以尝试每两行计算一次外汇的平均值:

result = df.groupby(np.arange(len(df))//2).mean()

print(result)

   egystart    egyend    fx
0 -1.979005 -1.937020  0.30
1 -1.895035 -1.853045  0.45
2 -1.811060 -1.769075  0.50