The goal of calcal is to do calendrical calculations, based on the algorithms described in Reingold and Dershowitz (2018) Calendrical Calculations, 4th edition, Cambridge University Press.
It is largely a translation of the Lisp code produced by Reingold and Dershowitz for Calendrica 4.0.
Installation
You can install the stable version from CRAN with:
pak::pak("calcal")You can install the development version from GitHub with:
pak::pak("robjhyndman/calcal")Example
Dates in multiple calendars:
library(calcal)
library(tibble)
library(tidyr)
library(dplyr)
tibble(
Gregorian = gregorian_date(1990, 2, 20) + 1:10,
ISO = as_iso(Gregorian),
Islamic = as_islamic(Gregorian),
Hebrew = as_hebrew(Gregorian)
)
#> # A tibble: 10 × 4
#> Gregorian ISO Islamic Hebrew
#> <Gre> <ISO> <Hij> <Heb>
#> 1 1990-Feb-21 1990-08-03 1410-Raj-25 5750-Shevat-26
#> 2 1990-Feb-22 1990-08-04 1410-Raj-26 5750-Shevat-27
#> 3 1990-Feb-23 1990-08-05 1410-Raj-27 5750-Shevat-28
#> 4 1990-Feb-24 1990-08-06 1410-Raj-28 5750-Shevat-29
#> 5 1990-Feb-25 1990-08-07 1410-Raj-29 5750-Shevat-30
#> 6 1990-Feb-26 1990-09-01 1410-Raj-30 5750-Adar-01
#> 7 1990-Feb-27 1990-09-02 1410-Sha-01 5750-Adar-02
#> 8 1990-Feb-28 1990-09-03 1410-Sha-02 5750-Adar-03
#> 9 1990-Mar-01 1990-09-04 1410-Sha-03 5750-Adar-04
#> 10 1990-Mar-02 1990-09-05 1410-Sha-04 5750-Adar-05Some religious and cultural holidays
tibble(
year = 2025:2028,
# Christian holidays
Easter = easter(year),
`Orthodox Easter` = orthodox_easter(year),
Christmas = christmas(year),
`Orthodox Christmas` = orthodox_christmas(year),
# Jewish holidays
`Rosh Hashanah` = rosh_hashanah(year),
Passover = passover(year),
`Yom Kippur` = yom_kippur(year),
Sukkot = sukkot(year),
Hanukkah = hanukkah(year),
# Islamic holidays
Ramadan = ramadan(year),
`Eid al-Fitr` = eid_al_fitr(year),
`Eid al-Adha` = eid_al_adha(year),
# Chinese Holidays
`Chinese New Year` = chinese_new_year(year),
`Dragon Festival` = dragon_festival(year),
`Qing Ming` = qing_ming(year),
# Hindu Holidays
`Hindu Lunar New Year` = hindu_lunar_new_year(year),
`Hindu Solar New Year` = mesha_sankranti(year),
Diwali = diwali(year),
Rama = rama(year),
Shiva = shiva(year)
) |>
pivot_longer(-year) |>
pivot_wider(names_from = year, values_from = value) |>
arrange(`2025`)
#> # A tibble: 20 × 5
#> name `2025` `2026` `2027` `2028`
#> <chr> <Gre> <Gre> <Gre> <Gre>
#> 1 Orthodox Christmas 2025-Jan-07 2026-Jan-07 2027-Jan-07 2028-Jan-07
#> 2 Chinese New Year 2025-Jan-29 2026-Feb-17 2027-Feb-06 2028-Jan-26
#> 3 Shiva 2025-Feb-27 2026-Feb-16 2027-Mar-07 2028-Feb-24
#> 4 Ramadan 2025-Mar-01 2026-Feb-18 2027-Feb-08 2028-Jan-28
#> 5 Hindu Lunar New Year 2025-Mar-30 2026-Mar-19 2027-Apr-07 2028-Mar-27
#> 6 Eid al-Fitr 2025-Mar-31 2026-Mar-20 2027-Mar-10 2028-Feb-27
#> 7 Qing Ming 2025-Apr-04 2026-Apr-05 2027-Apr-05 2028-Apr-04
#> 8 Rama 2025-Apr-06 2026-Mar-27 2027-Apr-15 2028-Apr-04
#> 9 Passover 2025-Apr-13 2026-Apr-02 2027-Apr-22 2028-Apr-11
#> 10 Hindu Solar New Year 2025-Apr-14 2026-Apr-14 2027-Apr-14 2028-Apr-13
#> 11 Easter 2025-Apr-20 2026-Apr-05 2027-Mar-28 2028-Apr-16
#> 12 Orthodox Easter 2025-Apr-20 2026-Apr-12 2027-May-02 2028-Apr-16
#> 13 Dragon Festival 2025-May-31 2026-Jun-19 2027-Jun-09 2028-May-28
#> 14 Eid al-Adha 2025-Jun-07 2026-May-27 2027-May-17 2028-May-05
#> 15 Rosh Hashanah 2025-Sep-23 2026-Sep-12 2027-Oct-02 2028-Sep-21
#> 16 Yom Kippur 2025-Oct-02 2026-Sep-21 2027-Oct-11 2028-Sep-30
#> 17 Sukkot 2025-Oct-07 2026-Sep-26 2027-Oct-16 2028-Oct-05
#> 18 Diwali 2025-Oct-22 2026-Nov-10 2027-Oct-30 2028-Nov-17
#> 19 Hanukkah 2025-Dec-15 2026-Dec-05 2027-Dec-25 2028-Dec-13
#> 20 Christmas 2025-Dec-25 2026-Dec-25 2027-Dec-25 2028-Dec-25