模型的特徵數量必須與輸入匹配。模型n_features是20，輸入n_features是4

Question

enter image description here我在使用隨機森林分類器時出現此錯誤。這裏是我的代碼：

import quandl, math  
import numpy as np  
import pandas as pd  
import matplotlib.pyplot as plt  
from matplotlib import style 
import datetime  
from sklearn.ensemble import RandomForestClassifier  
from sklearn.preprocessing import LabelEncoder  
from sklearn.feature_extraction.text import CountVectorizer 

train = pd.read_csv("train.csv", index_col=None)  
vectorizer = CountVectorizer(min_df=1)  
X1 = vectorizer.fit_transform(train['question'])  
X=X1.toarray()  
corpus=['tell me your name']  
t1= vectorizer.fit_transform(corpus)  
t=t1.toarray()  
number=LabelEncoder() 
train['answer']=number.fit_transform(train['answer'].astype('str'))  
features = ['question','answer']  
y= train['question'].values  
clf=RandomForestClassifier(n_estimators=20)  
clf.fit(X,y)  
predicted_result=clf.predict(t) 

Answer 1

對列車和測試數據都使用相同的訓練矢量。第二次，如果你再次適合數據，那麼它會根據這個新數據將它變成矢量。

X1 = vectorizer.fit_transform(train['question']) 
t1= vectorizer.transform(corpus)