era: Year-Based Time Scales

Provides a consistent representation of year-based time scales as a numeric vector with an associated 'era'. There are built-in era definitions for many year numbering systems used in contemporary and historic calendars (e.g. Common Era, Islamic 'Hijri' years); year-based time scales used in archaeology, astronomy, geology, and other palaeosciences (e.g. Before Present, SI-prefixed 'annus'); and support for arbitrary user-defined eras. Years can converted from any one era to another using a generalised transformation function. Methods are also provided for robust casting and coercion between years and other numeric types, type-stable arithmetic with years, and pretty-printing in tables.

Version: 0.4.1
Depends: R (≥ 2.10)
Imports: vctrs (≥ 0.3.0), methods, rlang, pillar
Suggests: tibble, testthat, covr, knitr, rmarkdown, dplyr, spelling, purrr, tidyr, lubridate
Published: 2022-11-17
DOI: 10.32614/CRAN.package.era
Author: Joe Roe ORCID iD [aut, cre]
Maintainer: Joe Roe <joe at>
License: MIT + file LICENSE
NeedsCompilation: no
Language: en-GB
Materials: README NEWS
In views: TimeSeries
CRAN checks: era results


Reference manual: era.pdf
Vignettes: Years with an era


Package source: era_0.4.1.tar.gz
Windows binaries: r-devel:, r-release:, r-oldrel:
macOS binaries: r-release (arm64): era_0.4.1.tgz, r-oldrel (arm64): era_0.4.1.tgz, r-release (x86_64): era_0.4.1.tgz, r-oldrel (x86_64): era_0.4.1.tgz
Old sources: era archive


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