date_range()#
relationalai.std.dates
#date_range(start: date | datetime | None = None, end: date | datetime | None = None, periods: int = 1, freq: str = "D") -> Expression
Creates a range of Date or DateTime values.
If both start and end arguments are provided, they must both be dates or both be datetimes.
Must be used within a rule or query context.
Parameters#
| Name | Type | Description |
|---|---|---|
start | date or datetime or None | Optional start of the range (default is None). If start and end are both provided, they must be of the same type. |
end | date or datetime or None | Optional end of the range (default is None). If start and end are both provided, they must be of the same type. |
periods | int | Optional number of periods in the range (default is 1). |
freq | str | The frequency of the periods (default is "D" for days). Accepted values are:
|
Returns#
An Expression that produces a range of Date or DateTime values.
Example#
Use the date_range() function to create various ranges of dates and datetimes.
Get a range of dates from January 1, 2024 to January 7, 2024:
#from relationalai.std.dates import date, date_range
# Create a model named "events" with an `Event` type.
model = rai.Model("events")
Event = model.Type("Event")
# Get a range of dates.
with model.query() as select:
# NOTE: 'start' and 'end' must be of the same type.
dates = date_range(date(2024, 1, 1), date(2024, 1, 7))
response = select(dates)
print(response.results)
# v
# 0 2024-01-01
# 1 2024-01-02
# 2 2024-01-03
# 3 2024-01-04
# 4 2024-01-05
# 5 2024-01-06
# 6 2024-01-07
You can use DateTime values instead of Date values:
#from relationalai.std.dates import datetime, date_range
# Get a range of datetimes with hourly frequency.
with model.query() as select:
times = date_range(
start=datetime(2024, 1, 1, 0, 0, 0),
end=datetime(2024, 1, 1, 12, 0, 0),
freq="H"
)
response = select(times)
print(response.results)
# v
# 0 2024-01-01 00:00:00
# 1 2024-01-01 01:00:00
# 2 2024-01-01 02:00:00
# 3 2024-01-01 03:00:00
# 4 2024-01-01 04:00:00
# 5 2024-01-01 05:00:00
# 6 2024-01-01 06:00:00
# 7 2024-01-01 07:00:00
# 8 2024-01-01 08:00:00
# 9 2024-01-01 09:00:00
# 10 2024-01-01 10:00:00
# 11 2024-01-01 11:00:00
# 12 2024-01-01 12:00:00
Using a sub-day frequency with a Date value produces a range of DateTime values:
#from relationalai.std.dates import date, date_range
# Get a range of datetimes with hourly frequency.
with model.query() as select:
times = date_range(date(2024, 1, 1), date(2024, 1, 2), freq='H')
response = select(times)
print(response.results)
# v
# 0 2024-01-01 00:00:00
# 1 2024-01-01 01:00:00
# 2 2024-01-01 02:00:00
# 3 2024-01-01 03:00:00
# 4 2024-01-01 04:00:00
# 5 2024-01-01 05:00:00
# 6 2024-01-01 06:00:00
# 7 2024-01-01 07:00:00
# 8 2024-01-01 08:00:00
# 9 2024-01-01 09:00:00
# 10 2024-01-01 10:00:00
# 11 2024-01-01 11:00:00
# 12 2024-01-01 12:00:00
# 13 2024-01-01 13:00:00
# 14 2024-01-01 14:00:00
# 15 2024-01-01 15:00:00
# 16 2024-01-01 16:00:00
# 17 2024-01-01 17:00:00
# 18 2024-01-01 18:00:00
# 19 2024-01-01 19:00:00
# 20 2024-01-01 20:00:00
# 21 2024-01-01 21:00:00
# 22 2024-01-01 22:00:00
# 23 2024-01-01 23:00:00
# 24 2024-01-02 00:00:00
Create a range without an end date by specifying only the number of periods:
#from relationalai.std.dates import datetime, date_range
# Create a range without an end date.
with model.query() as select:
times = date_range(datetime(2024, 1, 1, 0, 0, 0, 0), periods=3, freq='D')
response = select(times)
print(response.results)
# v
# 0 2024-01-01
# 1 2024-01-02
# 2 2024-01-03
Create a range that ends at a specified end date:
#from relationalai.std.dates import date, date_range
# Create a range that ends at the specified end date.
with model.query() as select:
dates = date_range(end=date(2024, 1, 7), periods=7, freq='D')
response = select(dates)
print(response.results)
# v
# 0 2024-01-01
# 1 2024-01-02
# 2 2024-01-03
# 3 2024-01-04
# 4 2024-01-05
# 5 2024-01-06
# 6 2024-01-07