Python中基于数据帧特征的计算？

我的数据框架如下所示：

df = pd.DataFrame({"ID" : ["1", "2", "2", "1", "3"],
                    "currency" : ["GBP", "GBP", "GBP", "CHF", "EUR"],
                    "amount" : [100, 200, 300, 400, 500]})

我需要计算：

New1=使用英镑货币的协议数量

New2=使用英镑货币的协议金额

我需要的结果如下：

df = pd.DataFrame({"ID" : ["1", "2", "2", "1", "3"],
                    "currency" : ["GBP", "GBP", "GBP", "CHF", "EUR"],
                    "amount" : [100, 200, 300, 400, 500]})

---

我们可以先进行筛选，然后再执行

groupby

和

reindex

out = df.loc[df.currency=='GBP'].groupby(['ID']).amount.agg(['count','sum']).reindex(df.ID.unique())
Out[210]: 
    count    sum
ID              
1     1.0  100.0
2     2.0  500.0
3     NaN    NaN

你可以试试这个-

import pandas as pd

df = pd.DataFrame({"ID" : ["1", "2", "2", "1", "3"],
                    "currency" : ["GBP", "GBP", "GBP", "CHF", "EUR"],
                    "amount" : [100, 200, 300, 400, 500]})

>>> pd.pivot_table(df.loc[df.currency=='GBP'],index=["ID"],aggfunc={'currency':'count','amount':'sum'}).reindex(df.ID.unique()).reset_index()
   
ID  amount  currency                
1    100.0       1.0
2    500.0       2.0
3      NaN       NaN