创建函数为DATE列生成TIME列，标记月度与季度标签

Pandas（Python） #

先把字符串格式的日期转为datetime类型，再提取月份生成对应标签：

import pandas as pd

# 假设数据存在DataFrame df中
df['DATE'] = pd.to_datetime(df['DATE'], format='%m/%d/%Y')
df['TIME'] = df['DATE'].dt.month.apply(lambda x: 'quarterly, monthly' if x in {1,4,7,10} else 'monthly')

SQL #

若DATE列是字符串格式（MM/DD/YYYY） #

SELECT
    DATE,
    CASE
        WHEN MONTH(STR_TO_DATE(DATE, '%m/%d/%Y')) IN (1,4,7,10)
        THEN 'quarterly, monthly'
        ELSE 'monthly'
    END AS TIME
FROM your_table_name;

若DATE列已为日期类型 #

SELECT
    DATE,
    CASE
        WHEN MONTH(DATE) IN (1,4,7,10)
        THEN 'quarterly, monthly'
        ELSE 'monthly'
    END AS TIME
FROM your_table_name;

Excel #

若DATE列是文本格式 #

在目标单元格（如B2）输入公式后下拉填充：

=IF(OR(MONTH(DATEVALUE(A2))=1,MONTH(DATEVALUE(A2))=4,MONTH(DATEVALUE(A2))=7,MONTH(DATEVALUE(A2))=10),"quarterly, monthly","monthly")

若DATE列已为日期格式 #

简化公式：

=IF(OR(MONTH(A2)=1,MONTH(A2)=4,MONTH(A2)=7,MONTH(A2)=10),"quarterly, monthly","monthly")

内容的提问来源于stack exchange，提问作者nick1