一旦达到阈值，累积的pandas列就会“重置”

import pandas as pd

# 创建示例数据
data = {'日期': ['2022-01-01', '2022-01-02', '2022-01-03', '2022-01-04'],
        '销售额': [500, 600, 400, 700],
        '累积销售额': [500, 1100, 1500, 2200]}

df = pd.DataFrame(data)

# 定义阈值
threshold = 1000

# 遍历每一行
for i in range(len(df)):
    # 判断累积销售额是否达到阈值
    if df.loc[i, '累积销售额'] >= threshold:
        # 将累积销售额重置为0
        df.loc[i, '累积销售额'] = 0

print(df)

           日期  销售额  累积销售额
0  2022-01-01  500      500
1  2022-01-02  600        0
2  2022-01-03  400        0
3  2022-01-04  700      700