convert_sequence: Sequence method for messydates

In messydates: A Flexible Class for Messy Dates

Sequence method for messydates

Description

This function provides a sequence (seq()) method for messydates. This can be used with ranges or unspecified dates, and is particularly useful for defining a sequence of dates before the common era or between eras.

Usage

## S3 method for class 'mdate'
seq(from, to, by = "days", ...)

Arguments

from	A messydate or range. If 'from' is a range and 'to' is not specified, 'from' will be the minimum of the range and 'to' will be maximum.
to	A messydate.
by	Increment of the sequence. By default "days". Use a sub-day unit ("hour", "min", or "sec") for a date-time sequence.
...	Arguments passed to or from methods.

Details

If from/to (or by) carry a time of day, the sequence is generated at the requested sub-day granularity (e.g. by = "hour") via POSIXct, and each element of the result keeps a time of day. Otherwise, dates are sequenced by calendar day (or another day-based by, e.g. "week" or "month"), including across the boundary between BCE and CE dates.

Examples

seq(mdate("-0001-12-20"), mdate("0001-01-10"))
# a range's endpoints are used when only 'from' is given
seq(as_messydate("2012-01-01..2012-01-05"))
# date-time sequences use a sub-day 'by'
seq(as_messydate("2019-03-01 09:00"), as_messydate("2019-03-01 12:00"),
    by = "hour")

messydates documentation built on July 17, 2026, 1:07 a.m.