Question

我创建了下面的函数，它根据两个输入向量返回一个向量。我有一个包含不同列的pandas数据帧，我想将该函数应用于我的数据帧的某些列（一个pandas列将是我的函数的第一个向量（标称值），另一个是我的函数的第二个向量（CPI）和我会将我的函数的结果分配给一个新的pandas列）。我怎么能这样做？

非常感谢你的帮助，

皮埃尔

nominal=[10,10,10,10,10,10,10,10,10,10,10,10]
CPI=[0.02,0.02,0.02,0.02,0.02,0.02,0.02,0.02,0.02,0.02,0.02,0.02]

def nominal_to_real(nominal,CPI):
    real=[]
    product=1
    for i in range(len(nominal)):
        product*=(CPI[i]+1)**(1/12)     
        real.append(nominal[i]/product)
    return real

Answer 1

您可以将cumprod用于矢量化解决方案：

nominal=[10,10,10,10,10,10,10,10,10,10,10,10]
CPI=[0.02,0.02,0.02,0.02,0.02,0.02,0.02,0.02,0.02,0.02,0.02,0.02]

def nominal_to_real(nominal,CPI):
    real=[]
    product=1
    for i in range(len(nominal)):
        product*=(CPI[i]+1)**(1/12)     
        real.append(nominal[i]/product)
    return real

a = nominal_to_real(nominal,CPI)
df = pd.DataFrame(np.c_[nominal, CPI, a], columns=['nominal','CPI','real'])

df['real1'] = df['nominal'] / ((df['CPI'] + 1)**(1/12)).cumprod() 
print (df)
    nominal   CPI      real     real1
0      10.0  0.02  9.983511  9.983511
1      10.0  0.02  9.967050  9.967050
2      10.0  0.02  9.950616  9.950616
3      10.0  0.02  9.934209  9.934209
4      10.0  0.02  9.917829  9.917829
5      10.0  0.02  9.901475  9.901475
6      10.0  0.02  9.885149  9.885149
7      10.0  0.02  9.868850  9.868850
8      10.0  0.02  9.852578  9.852578
9      10.0  0.02  9.836332  9.836332
10     10.0  0.02  9.820114  9.820114
11     10.0  0.02  9.803922  9.803922

在pandas列上应用函数

1 个答案: