Measurement Units for R
News
Cite this package as Edzer Pebesma, Thomas Mailund
and James Hiebert, 2016. Measurement Units in R.
The R Journal, 8 (2), 486--494. The citation is found
here.
The units vignette is derived from this manuscript, and is kept up
to date with the package.
What it does
Package units 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 5
spd1 + spd2 # automatic conversion
# Units: m/s
# [1] 1.277778 2.555556 3.833333 5.111111 6.388889
spd1 * spd2 # unit derivation
# Units: km*m/h/s
# [1] 1 4 9 16 25
spd1 * set_units(10, s) # unit simplification
# Units: m
# [1] 10 20 30 40 50
spd1 + set_units(10, s) # error checking
# cannot convert s into m/s
- blog posts: first, second, third
- package vignette
- The R Journal publication, which has been updated to recent package developments
- the udunits2 R package github page
- the UNIDATA udunits2 library at github
When installing the udunits2 R package fails due to a missing
udunits2 system library, either install it binary e.g. by
sudo apt-get install libudunits2-dev
or install from source by downloading udunits-2.2.20.tar.gz from
ftp://ftp.unidata.ucar.edu/pub/udunits/, and executing the
following commands in the download directory:
tar zxf udunits-2.2.20.tar.gz
cd ./udunits-2.2.20/
./configure
make
sudo make install
sudo ldconfig
if that went well, assuming you installed by default in /usr/local/, add
export UDUNITS2_XML_PATH="/usr/local/share/udunits/udunits2.xml"
to your ~/.bashrc file, start a new shell to activate this environment variable, and try installing R package udunits2 once more. When launching rstudio from unity, you may have to load udunits2 explicitly before using units, or set UDUNITS2_XML_PATH in a different way such that rstudio finds it.