Author: Chi Zhang
Date: 2021-09-15

# Intro to cstime

#### Chi Zhang

#### 2021-09-15

`cstime` provides date time functions for public health purposes.

The core functionality is consistent time conversion between :

- Date.
- Isoyear, isoweek, isoyearweek.
- Season week.

It also provides functions to generate rolling dates for computing the weekly, bi-weekly, 4 week averages.

`cstime` is part of the csverse package suite.

    library(cstime)
    #> cstime 2023.5.3
    #> https://www.csids.no/cstime/
    library(magrittr)

To convert a date to isoyear:

    date_to_isoyear_c('2021-01-01')
    #> [1] "2020"

To convert a isoyearweek string to isoyear/isoweek:

    isoyearweek_to_isoyear_c("2021-02")
    #> [1] "2021"
    isoyearweek_to_isoweek_c("2021-02")
    #> [1] "02"

To convert a season week to isoweek (and reverse):

    seasonweek_to_isoweek_n(10)
    #> [1] 10
    isoweek_to_seasonweek_n(1)
    #> [1] 24