I have a column Date_Time
that I wish to groupby date time without creating a new column. Is this possible the current code I have does not work.
df = pd.groupby(df,by=[df['Date_Time'].date()])
You can use groupby
by dates of column Date_Time
by dt.date
:
df = df.groupby([df['Date_Time'].dt.date]).mean()
Sample:
df = pd.DataFrame({'Date_Time': pd.date_range('10/1/2001 10:00:00', periods=3, freq='10H'),
'B':[4,5,6]})
print (df)
B Date_Time
0 4 2001-10-01 10:00:00
1 5 2001-10-01 20:00:00
2 6 2001-10-02 06:00:00
print (df['Date_Time'].dt.date)
0 2001-10-01
1 2001-10-01
2 2001-10-02
Name: Date_Time, dtype: object
df = df.groupby([df['Date_Time'].dt.date])['B'].mean()
print(df)
Date_Time
2001-10-01 4.5
2001-10-02 6.0
Name: B, dtype: float64
Another solution with resample
:
df = df.set_index('Date_Time').resample('D')['B'].mean()
print(df)
Date_Time
2001-10-01 4.5
2001-10-02 6.0
Freq: D, Name: B, dtype: float64