Question

我想对每天分组的数据应用条件函数：对于每天有一半以上等于0的值的每一列，请将当天列的所有值设置为np.nan < / p>

date,value1,value2
2016-01-01 09:00:00,14,14
2016-01-01 10:00:00,12,13
2016-01-01 11:00:00,11,13
2016-01-01 12:00:00,11,9
2016-01-01 13:00:00,17,21
2016-01-01 14:00:00,9,22
2016-01-01 15:00:00,10,9
2016-01-01 16:00:00,11,9
2016-01-01 17:00:00,8,8
2016-01-01 18:00:00,4,2
2016-01-01 19:00:00,5,7
2016-01-01 20:00:00,5,5
2016-01-01 21:00:00,3,4
2016-01-01 22:00:00,2,4
2016-01-01 23:00:00,2,4
2016-01-02 09:00:00,0,0
2016-01-02 10:00:00,0,0
2016-01-02 11:00:00,0,0
2016-01-02 12:00:00,0,0
2016-01-02 13:00:00,1,0
2016-01-02 14:00:00,0,0
2016-01-02 15:00:00,0,0
2016-01-02 16:00:00,0,0
2016-01-02 17:00:00,0,0
2016-01-02 18:00:00,0,0
2016-01-02 19:00:00,0,0
2016-01-02 20:00:00,1,0
2016-01-02 21:00:00,0,0
2016-01-02 22:00:00,0,0
2016-01-02 23:00:00,0,0

所需的输出：

date,value1,value2
2016-01-01 09:00:00,14,14
2016-01-01 10:00:00,12,13
2016-01-01 11:00:00,11,13
2016-01-01 12:00:00,11,9
2016-01-01 13:00:00,17,21
2016-01-01 14:00:00,9,22
2016-01-01 15:00:00,10,9
2016-01-01 16:00:00,11,9
2016-01-01 17:00:00,8,8
2016-01-01 18:00:00,4,2
2016-01-01 19:00:00,5,7
2016-01-01 20:00:00,5,5
2016-01-01 21:00:00,3,4
2016-01-01 22:00:00,2,4
2016-01-01 23:00:00,2,4
2016-01-02 09:00:00,null,null
2016-01-02 10:00:00,null,null
2016-01-02 11:00:00,null,null
2016-01-02 12:00:00,null,null
2016-01-02 13:00:00,null,null
2016-01-02 14:00:00,null,null
2016-01-02 15:00:00,null,null
2016-01-02 16:00:00,null,null
2016-01-02 17:00:00,null,null
2016-01-02 18:00:00,null,null
2016-01-02 19:00:00,null,null
2016-01-02 20:00:00,null,null
2016-01-02 21:00:00,null,null
2016-01-02 22:00:00,null,null
2016-01-02 23:00:00,null,null

我已经阅读了以下问题：pandas apply function to data grouped by day，并试图遵循：

df_mode = df.groupby(df.index.date).apply(lambda x: mode(x)[0])

在每一列中，我每天获得的最频繁的值。但是我不知道如何进行下一步（将当天列中的所有值都设置为np.nan）

在这种情况下，有没有比使用apply更有效的方法了？

谢谢

Answer 1

将GroupBy.transform与比较值分别为var nonEmoji = new RegExp(/[\ud83c[\udf00-\udfff]|\ud83d[\udc00-\ude4f]|\ud83d[\ude80-\udeff]]*$/, 'i');和0的百分比，然后通过DataFrame.mask设置最小值：

mean

在熊猫中按天分组的数据应用条件函数的有效方法

1 个答案: