A lookup table with one row per ISO yearweek, for ISO years 1900 to 2099. Each row holds the date of every day of that week, Monday to Sunday, plus list-columns that group those dates. The 10436 rows run from "1900-01" to "2099-53", so the dates covered are 1900-01-01 to 2100-01-03.
Format
A data.table::data.table with one row per ISO yearweek and the following columns:
- isoyear
Integer. ISO year.
- isoyearweek
Character. ISO yearweek, "yyyy-ww".
- mon
Date of Monday.
- tue
Date of Tuesday.
- wed
Date of Wednesday.
- thu
Date of Thursday.
- fri
Date of Friday.
- sat
Date of Saturday.
- sun
Date of Sunday.
- weekdays
List column. The dates Monday to Friday.
- weekend
List column. The dates Saturday and Sunday.
- days
List column. The dates Monday to Sunday.
Source
Generated from a daily date sequence using ISO 8601 week rules. See
data-raw/1_gen-data.R in the package source.
Examples
library(data.table)
#>
#> Attaching package: ‘data.table’
#> The following object is masked from ‘package:base’:
#>
#> %notin%
# Look up the Monday and Sunday of two ISO yearweeks
dates_by_isoyearweek[isoyearweek %in% c("2021-01", "2021-02"), .(isoyearweek, mon, sun)]
#> isoyearweek mon sun
#> <char> <Date> <Date>
#> 1: 2021-01 2021-01-04 2021-01-10
#> 2: 2021-02 2021-01-11 2021-01-17
# Constructing a vector of dates without removing the Date class
do.call("c", dates_by_isoyearweek[isoyearweek %in% c("2021-01", "2021-02")]$weekdays)
#> [1] "2021-01-04" "2021-01-05" "2021-01-06" "2021-01-07" "2021-01-08"
#> [6] "2021-01-11" "2021-01-12" "2021-01-13" "2021-01-14" "2021-01-15"