获取熊猫的人力资源计数

Question

我有一个熊猫数据框，如下所示：

    |       Date        |
    +-------------------+
    |2009-11-01 00:00:08|
    |2009-11-01 00:00:40|
    |2009-11-01 01:00:20|
    |2009-11-01 01:50:08|
    |2009-11-01 02:22:00|
    |2009-11-01 02:45:50|
    |2009-11-01 03:10:20|
    |2009-11-01 03:20:30|
    +-------------------+

我想要如下所示的hr计数：

    |       Hr          |  Count |
    +-------------------+--------+
    |00:00:00 - 00:59:59|   2    |
    |01:00:00 - 01:59:59|   2    |
    |02:00:00 - 02:59:59|   2    |
    |03:00:00 - 03:59:59|   2    |
    +-------------------+--------+

那么，我如何使用pandas dataframe获得计数呢？

Answer 1

df["Date"] = pd.to_datetime(df["Date"])
df["hour"] = df.Date.dt.hour

df_out = (
    df.groupby("hour")
    .agg(
        {
            "Date": lambda x: "{h:02d}:00:00 - {h:02d}:59:59".format(
                h=x.iat[0].hour
            ),
            "hour": "size",
        }
    )
    .rename(columns={"Date": "Hr", "hour": "Count"})
    .reset_index(drop=True)
)
print(df_out)

打印：

                    Hr  Count
0  00:00:00 - 00:59:59      2
1  01:00:00 - 01:59:59      2
2  02:00:00 - 02:59:59      2
3  03:00:00 - 03:59:59      2