python-3.x - 特征数错误。如何解决这个问题？

Question

请帮忙，我收到一些功能错误。使用的列是 ID、编码列和整数列。此代码适用于具有相似但更多功能的另一个数据集。使用的功能数量是否太少而无法出现此错误？这是我的代码：

from sklearn.model_selection import train_test_split
num_test = 0.20  # 80-20 split
X_train, X_test, y_train, y_test = train_test_split(X_all, y_all, test_size=num_test, random_state=23)
from sklearn.ensemble import RandomForestClassifier
from sklearn.metrics import make_scorer, accuracy_score
from sklearn.model_selection import GridSearchCV
clf = RandomForestClassifier()
parameters = {'n_estimators': [4, 6, 9],
              'max_features': ['log2', 'sqrt', 'auto'],
              'criterion': ['entropy', 'gini'],
              'max_depth': [2, 3, 5, 10],
              'min_samples_split': [2, 3, 5],
              'min_samples_leaf': [1, 5, 8]
              }

acc_scorer = make_scorer(accuracy_score)

grid_obj = GridSearchCV(clf, parameters, scoring=acc_scorer)
grid_obj = grid_obj.fit(X_train, y_train)

clf = grid_obj.best_estimator_
clf.fit(X_train, y_train)
ids = data_test['Id']
predictions = clf.predict(data_test.drop('Id', axis=1))
output = pd.DataFrame({'Id': ids, 'Full_Time_Home_Goals': predictions})

print(output.head())

我得到的错误是：

> Traceback (most recent call last):
>       File "C:/Users/harsh/PycharmProjects/Kaggle-Machine Learning from Start to Finish with Scikit-Learn/EPL Predicting.py", line 98, in
> <module>
>         predictions = clf.predict(data_test.drop('Id', axis=1))
>       File "C:\Users\harsh\PycharmProjects\GitHub\venv\lib\site-packages\sklearn\ensemble\_forest.py",
> line 629, in predict
>     ValueError: Number of features of the model must match the input. Model n_features is 4 and input n_features is 2

即使我不放弃predictions = clf.predict(data_test.drop('Id', axis=1))，我仍然会收到错误

样本数据集：

data_train:
   Id  HomeTeam  AwayTeam  Full_Time_Home_Goals
0   1        55       440                     3
1   2       158       493                     2
2   3       178       745                     1
3   4       185       410                     1
4   5       249        57                     2

data_test:
       Id  HomeTeam  AwayTeam
0  190748       284        54
1  190749       124       441
2  190750       446        57
3  190751       185       637
4  190752       749       482

列是它应该工作的方式。为什么不是？

标签： python-3.xscikit-learnpredict