Add astronomical year units #15

Sidereal, tropical and anomalistic
joeroe · Jan 29, 2021 · b6f268d · b6f268d
1 parent 75c56be
commit b6f268d
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/data-raw/era_table.R b/data-raw/era_table.R
@@ -4,11 +4,15 @@ library("tibble")
 library("usethis")
 
 # Unit definitions
+# Mostly from https://en.wikipedia.org/wiki/Year
 gregorian <- era_year("Gregorian", 365.2425)
 julian <- era_year("Julian", 365.25)
 solar <- era_year("solar", 365.24219)
 islamic_lunar <- era_year("Islamic lunar", 354.36708)
 radiocarbon <- era_year("radiocarbon", NA)
+sidereal <- era_year("sidereal", 365.256363004)
+tropical <- era_year("tropical", 365.24219)
+anomalistic <- era_year("anomalistic", 365.259636)
 
 era_table <- tribble(
   # label must be unique