交叉验证评分可视化

def solve():
    import pandas as pd
    import matplotlib.pyplot as plt
    from sklearn.svm import SVC
    from sklearn.model_selection import cross_val_score
    df = pd.read_csv("https://data.zuihe.com/breast_cancer.csv")
    X = df.drop("target", axis=1); y = df["target"]
    scores = cross_val_score(SVC(random_state=42), X, y, cv=5)
    plt.boxplot(scores); plt.ylabel("Accuracy"); plt.title("Cross-Validation Scores")
    plt.show()
    print(f"{scores.mean():.4f}±{scores.std():.4f}")