基于同一数据框中的多个条件创建新列

import pandas as pd

# 创建示例数据框
data = {
    '姓名': ['张三', '李四', '王五', '赵六'],
    '数学': [90, 80, 70, 60],
    '英语': [85, 75, 65, 55]
}
df = pd.DataFrame(data)

# 定义成绩等级的条件
def grade_level(math, english):
    if math >= 90 and english >= 90:
        return 'A+'
    elif math >= 80 and english >= 80:
        return 'A'
    elif math >= 70 and english >= 70:
        return 'B'
    else:
        return 'C'

# 应用条件逻辑创建新列
df['成绩等级'] = df.apply(lambda row: grade_level(row['数学'], row['英语']), axis=1)

print(df)

import numpy as np

conditions = [
    (df['数学'] >= 90) & (df['英语'] >= 90),
    (df['数学'] >= 80) & (df['英语'] >= 80),
    (df['数学'] >= 70) & (df['英语'] >= 70)
]
choices = ['A+', 'A', 'B']
df['成绩等级'] = np.select(conditions, choices, default='C')