README.md
In ethiodate: Working with Ethiopian Dates

ethiodate

This package enables you to work with Ethiopian dates in R like you do with base R Date objects. It can seamlessly convert to and from Gregorian dates, regardless of the way you record them. It supports almost all important parsing techniques used for a base R Date object. If you have ever worked with a Date object, you can do the same with Ethiopian dates. It is designed to work smoothly with the {tidyverse}, including {ggplot2}, {dplyr}, {tibble}, and {lubridate}, making it ideal for data manipulation pipelines. This package ensures lightning-fast computations thanks to the {Rcpp} package that enables the integration of high-performance C++ code. It has built-in checks for leap years and the 13th month (Pagume), which makes this package crucial.

Custom Date Object: You can convert your date recorded in any style to custom ethdate object.
Seamless Date Conversion: Effortlessly convert Ethiopian dates to and from Gregorian dates with precision.
High-Speed Computation: Written in C++ for maximum efficiency.
Date Arithmetic: Perform date arithmetic operations.
Day-Based Units: Dates are represented as the number of days since 1963-04-23 EC (1970-01-01 GC) to simplify conversion between calendars.
Integration with {ggplot2}: Designed to smoothly work with {ggplot2}.

You can install the development version of ethiodate package like so:

# Install the current version on CRAN
install.packages("ethiodate")

# Install a stable development version from GitHub (requires compilation)
devtools::install_github("GutUrago/ethiodate")

This package is for you if you have ever faced the following conditions, where;

You recorded Ethiopian year, month and days as a separate variable and not sure if the combination is valid date.
You recorded Ethiopian date as “dd-mm-yy”, “yy/mm/dd”, … etc, and you can’t perform any operations beyond string operations.
You have Ethiopian dates in any of above listed format and want to convert it to Gregorian dates.
You have Gregorian dates object and want to obtain equivalent Ethiopian dates.
You want to do some arithmetic operations with Ethiopian dates.
You want to build and present nicely formatted plots for time trends in local context.

Examples:

library(ethiodate)
library(dplyr)

data.frame(
  eth_year = c(2000, 2007, 2015, 2020, 1950, 2030),
  eth_month = c(8, 2, 13, 5, 7, 5),
  eth_day = c(25, 12, 6, 8, 17, 30)
) |> 
  mutate(
    eth_date = eth_make_date(eth_year, eth_month, eth_day),
    gre_date = as.Date(eth_date),
    eth_dayname = eth_weekday(eth_date, lang = "en"), 
    gre_dayname = weekdays(gre_date) 
  )
#>   eth_year eth_month eth_day   eth_date   gre_date eth_dayname gre_dayname
#> 1     2000         8      25 2000-08-25 2008-05-03    Saturday    Saturday
#> 2     2007         2      12 2007-02-12 2014-10-22   Wednesday   Wednesday
#> 3     2015        13       6 2015-13-06 2023-09-11      Monday      Monday
#> 4     2020         5       8 2020-05-08 2028-01-17      Monday      Monday
#> 5     1950         7      17 1950-07-17 1958-03-26   Wednesday   Wednesday
#> 6     2030         5      30 2030-05-30 2038-02-07      Sunday      Sunday