收到错误“未定义名称'y_test'”

Question

机器学习的新手，我试图找出accuracy score使用线性模型accuracy_score(y_test,y_pred)的定义。但是出现错误“名称'y_test'未定义”。谁能帮我这个？变量的定义如下：X_train, X_test, y_train, y_test = train_test_split(x, y, random_state=123)y_pred = linreg.predict(X_test)详细的错误消息。NameError Traceback（最近一次通话最后一次）在（）1中用于检查准确性和详细信息2从sklearn.metrics导入precision_score ----> 3 precision_score（y_test，y_pred）NameError：名称“ y_test”未定义在这里保存代码...#creating a function for modelsfrom sklearn.model_selection import train_test_splitfrom sklearn import metrics#functiondef train_test_rmse(x,y):    x = Iris_data[x]    y = Iris_data[y]    X_train, X_test, y_train, y_test = train_test_split(x, y, test_size = 0.2,random_state=123)    linreg = LinearRegression()    linreg.fit(X_train, y_train)    y_pred = linreg.predict(X_test)    return np.sqrt(metrics.mean_squared_error(y_test, y_pred))print(train_test_rmse(['Sepal.Length'],['Sepal.Width']))print(train_test_rmse(['Petal.Length'],['Sepal.Width']))print(train_test_rmse(['Sepal.Length'],['Petal.Width']))print(train_test_rmse(['Petal.Length'],['Petal.Width'])) #this one has least rmseprint(train_test_rmse(['Sepal.Width'],['Sepal.Length']))print(train_test_rmse(['Petal.Width'],['Sepal.Width']))#for checking the accuracy and detailsfrom sklearn.metrics import accuracy_scoreaccuracy_score(y_test,y_pred)