Support for measurement units in R vectors, matrices and arrays: automatic propagation, conversion, derivation and simplification of units; raising errors in case of unit incompatibility. Compatible with the POSIXct, Date and difftime classes. Uses the UNIDATA udunits library and unit database for unit compatibility checking and conversion.
Documentation
Documentation is provided in an R Journal publication. Cite this package as:
- Edzer Pebesma, Thomas Mailund and James Hiebert (2016). “Measurement Units in R.”The R Journal, 8 (2), 486–494. DOI:10.32614/RJ-2016-061
The main unitsvignette derives from this manuscript and is kept up to date with the package development.
What it does
Packageunits provides measurement units for R vectors: conversion, derivation, simplification and error checking:
library(units)(spd1=set_units(1:5,m/s))# Units: m/s# [1] 1 2 3 4 5(spd2=set_units(1:5,km/h))# Units: km/h# [1] 1 2 3 4 5spd1+spd2# automatic conversion# Units: m/s# [1] 1.277778 2.555556 3.833333 5.111111 6.388889spd1*spd2# unit derivation# Units: km*m/h/s# [1] 1 4 9 16 25spd1*set_units(10,s)# unit simplification# Units: m# [1] 10 20 30 40 50spd1+set_units(10,s)# error checking# cannot convert s into m/sInstallation
Install the release version from CRAN:
install.packages("units")The installation of the development version from GitHub requires, e.g., theremotes package:
remotes::install_github("r-quantities/units")If the installation fails due to a missing udunits2 system library, either install it e.g. on Ubuntu or Debian by
sudo apt-get install libudunits2-devon Fedora or RHEL/CentOS with
sudo dnf install udunits2-develor on MacOS with
brew install udunitsor equivalent in your distribution. Alternatively, install it from the sources by downloading the latest version fromUDUNITS downloads, and executing the following commands in the download directory:
tar zxf udunits-<version>.tar.gzcd ./udunits-<version>/./configuremakesudo make installsudo ldconfigThen, retry the installation ofunits.
