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 about 'units' is provided in the paper by Pebesma, Mailund &
Hiebert (2016, ), included in this package as a
vignette; see 'citation("units")' for details.