expand: Expand messy dates to lists of dates

In messydates: A Flexible Class for Messy Dates

Expand messy dates to lists of dates

Description

These functions expand on date ranges, sets of dates, and unspecified or approximate dates (annotated with '..', '', 'XX' or '~'). As these messydates may refer to several possible dates, the function "opens" these values to reveal a vector of all the possible dates implied. Imprecise dates (dates only containing information on year and/or month) are also expanded to include possible dates within that year and/or month. The function removes the annotation from dates with unreliable sources ('?'), before being expanded normally as though they were incomplete.

Usage

expand(x, approx_range = 0)

Arguments

x

A mdate object. If not an 'mdate' object, conversion is handled first with ´as_messydate()´.

approx_range

Range to expand approximate dates, or date components, annotated with '~', by default 0. That is, removes signs for approximate dates and treats these dates as precise dates. If 3, for example, adds 3 days for day approximation, 3 months for month approximation, 3 years for year/whole date approximation, 3 years and 3 months for year-month approximation, and 3 months and 3 days for month-day approximation.

Value

A list of dates, including all dates in each range or set.

Examples

d <- as_messydate(c("2008-03-25", "-2012-02-27", "2001-01?", "~2001",
"2001-01-01..2001-02-02", "{2001-01-01,2001-02-02}", "{2001-01,2001-02-02}",
"2008-XX-31", "..2002-02-03", "2001-01-03..", "28 BC"))
expand(d)

messydates documentation built on May 29, 2024, 2:16 a.m.