Time interval from a constant reference time in Pandas

Given a df

4
0
3
3
3

and reference ndata_time=’2019-01-15 7:00:00′,

I would to create a new column but with an interval of 5sec

4   2019-01-15 7:00.00
0   2019-01-15 7:00.05
3   2019-01-15 7:00.10
3   2019-01-15 7:00.15
3   2019-01-15 7:00.20

However, I am having difficulties of setting the interval_range() function in Pandas.

Appreciate if someone can shed some light.

import pandas as pd
np.random.seed(0)
ndata_time='2019-01-15 7:00:00'
lapse=5 # unit in second
df=pd.DataFrame(np.random.randint(5,size=(5)),columns=['data'])

>Solution :

You’d have to use pd.date_range here. Set period and freq parameter as needed.

• From Docs pd.date_range

periods: int, optional

• Number of periods to generate.

freq: str or DateOffset, default ‘D’

• Frequency strings can have multiples, e.g. ‘5H’. See here for a list of frequency aliases.

pd.date_range(start='2019-01-15 7:00:00', periods=5, freq='5S')

# DatetimeIndex(['2019-01-15 07:00:00', '2019-01-15 07:00:05',
#                '2019-01-15 07:00:10', '2019-01-15 07:00:15',
#                '2019-01-15 07:00:20'],
#               dtype='datetime64[ns]', freq='5S')