回归评估-R2分数

def solve():
    from sklearn.metrics import r2_score
    y_true = [3, 5, 7, 9]
    y_pred = [2.5, 5.5, 6.5, 9.5]
    r2 = r2_score(y_true, y_pred)
    print('R2分数:', round(r2, 4))