我有一个示例数据:
datetime temperature season
2021-04-10 01:00:00. 10. Heating season
2021-04-10 01:00:00. 26. Heating season
2021-07-10 01:00:00. 16. Cooling season
2021-07-10 01:00:00. 30. Cooling season
我想创建一个名为 new_temperature 的新列:a) 如果温度列小于 18 并且季节是采暖季节,则 new_temperature 应为 25,否则为 18 如果是冷却季节。 b) 如果温度列大于 25 且季节为冷季,则 new_temperature 列应为 18,否则为 22 为采暖季。
示例输出如下所示:
datetime temperature season. new_temperature
2021-04-10 01:00:00. 10. Heating season. 25
2021-04-10 01:00:00. 26. Heating season. 22
2021-07-10 01:00:00. 16. Cooling season. 18
2021-07-10 01:00:00. 30. Cooling season. 18
答案 0 :(得分:3)
np.select
有 4 个条件:
cond_1 = (df.temperature < 18) & (df.season == "Heating season")
cond_2 = (df.temperature < 18) & (df.season != "Heating season")
cond_3 = (df.temperature > 25) & (df.season == "Cooling season")
cond_4 = (df.temperature > 25) & (df.season != "Cooling season")
conditions = [cond_1, cond_2, cond_3, cond_4]
choices = [25, 18, 18, 22]
df["new_temperature"] = np.select(conditions, choices)
得到
datetime temperature season new_temperature
0 2021-04-10 01:00:00. 10.0 Heating season 25
1 2021-04-10 01:00:00. 26.0 Heating season 22
2 2021-07-10 01:00:00. 16.0 Cooling season 18
3 2021-07-10 01:00:00. 30.0 Cooling season 18
注意:由于您的条件不是互斥的,您可能希望为 default
提供一个 np.select
值作为最后一个参数。如果没有条件匹配,则将其放入结果中。