KNN-标准化前后对比

def solve():
    import pandas as pd
    from sklearn.neighbors import KNeighborsClassifier
    from sklearn.model_selection import train_test_split
    from sklearn.preprocessing import StandardScaler
    from sklearn.metrics import accuracy_score
    df = pd.read_csv(____)
    X = df.drop(____)
    y = df['____']
    X_train, X_test, y_train, y_test = train_test_split(____)
    knn1 = KNeighborsClassifier(____)
    knn1.fit(____)
    acc1 = accuracy_score(y_test, knn1.predict(____))
    scaler = StandardScaler()
    X_train_scaled = scaler.fit_transform(____)
    X_test_scaled = scaler.transform(____)
    knn2 = KNeighborsClassifier(____)
    knn2.fit(____)
    acc2 = accuracy_score(y_test, knn2.predict(____))
    print('____', round(____))
    print('____', round(____))