无法在 <module '__main__'> 上获取属性 'MyScaler'

Question

我的一个笔记本中有一个课程如下：

class MyScaler(BaseEstimator,TransformerMixin):
    def __init__(self,columns,with_mean=True,with_std=True,copy=True):
        self.scaler = StandardScaler(copy,with_mean,with_std)
        self.columns = columns
        self.mean_ = None
        self.var_ = None

    def fit(self,X,y=None):
        self.scaler.fit(X[self.columns],y)
        self.mean_ = np.array(np.mean(X[self.columns]))
        self.var_ = np.array(np.var(X[self.columns]))
        return self

    def transform(self,X,y=None,copy=None):
        initial_col_order = X.columns
        X_scaled = pd.DataFrame(self.scaler.transform(X[self.columns]),columns=self.columns)
        X_not_scaled = X.loc[:,~X.columns.isin(self.columns)]
        return pd.concat([X_not_scaled,X_scaled],axis=1)[initial_col_order]

我将这个类腌制为：

with open('Custom_Scaler','wb') as file:
    pickle.dump(MyScaler,file)

我有另一个模块“LogReg_Absent_Module”，我正在尝试取消腌制这个文件。我还在该模块中定义了这个类，如下所示：

import pandas as pd
import numpy as np
import pickle
from sklearn.preprocessing import StandardScaler
from sklearn.base import BaseEstimator, TransformerMixin

#The custom scaler that only scales the non-dummy value columns.
class MyScaler(BaseEstimator,TransformerMixin):
    def __init__(self,columns,with_mean=True,with_std=True,copy=True):
        self.scaler = StandardScaler(copy,with_mean,with_std)
        self.columns = columns
        self.mean_ = None
        self.var_ = None

    def fit(self,X,y=None):
        self.scaler.fit(X[self.columns],y)
        self.mean_ = np.array(np.mean(X[self.columns]))
        self.var_ = np.array(np.var(X[self.columns]))
        return self

    def transform(self,X,y=None,copy=None):
        initial_col_order = X.columns
        X_scaled = pd.DataFrame(self.scaler.transform(X[self.columns]),columns=self.columns)
        X_not_scaled = X.loc[:,~X.columns.isin(self.columns)]
        return pd.concat([X_not_scaled,X_scaled],axis=1)[initial_col_order]

#The class that we are going to use from here on to predict new data
class absenteeism_model():
    def __init__(self,model_file,scaler_file):
        with open('Absenteeism_Model','rb') as model_file,open('Custom_Scaler','rb') as scaler_file:
            self.log_reg = pickle.load(model_file)             #Load the previously saved model 
            self.scaler = pickle.load(scaler_file)             #and scaler.
            self.data = None

从一个新笔记本，当我尝试model = absenteeism_model('Absenteeism_Model','Custom_Scaler')

我明白了：

<ipython-input-66-8631c175353f> in <module>
----> 1 model = absenteeism_model('Absenteeism_Model','Custom_Scaler')

~\LogReg_Absent_Module.py in __init__(self, model_file, scaler_file)
    37         with open('Absenteeism_Model','rb') as model_file,open('Custom_Scaler','rb') as scaler_file:
    38             self.log_reg = pickle.load(model_file)             #Load the previously saved model
---> 39             self.scaler = pickle.load(scaler_file)             #and scaler.
    40             self.data = None
    41 

AttributeError: Can't get attribute 'MyScaler' on <module '__main__'>```

   

Answer 1

我不明白你为什么腌制一个类而不是那个类的对象

Answer 2

您介意展示您已实现 MyScaler 的部分代码吗？我认为在您保存缩放器时，您的 MyScaler 类的对象存在问题。

例如你已经声明：

scaler = MyScaler(X)

那么在这种情况下，您将使用以下代码进行腌制：

 with open ('Custom_Scaler' , 'wb') as file: 
  pickle.dump(scaler, file)

看看这是否能解决您的问题。