Changelog
Source:NEWS.md
constants 1.0.0
CRAN release: 2020-11-11
Update to version 8.1, the 2018 CODATA recommended values (#7 addressing #6). This version contains some breaking changes that are necessary to streamline future updates and provide a stable symbol table:
- The
codata
table includes the absolute uncertainty instead of the relative one. Thus, therel_uncertainty
column has been dropped in favour of the newuncertainty
. Also, columns have been slightly reordered. - Symbol names for constants have changed. The old ones were hand-crafted and thus unmanageable. This release adopts the ASCII symbols defined by NIST in their webpage, except for those that collide with some base R function. In particular, there are two cases:
c
, the speed of light, has been renamed asc0
;sigma
, the Stefan-Boltzmann constant, has been renamed assigma0
. - Constant types, or categories, (column
codata$type
) adopts the names defined by NIST in the webpage too. Some constants belong to more than one category (separated by comma); some others belong to no category (missing type).
There are some new features too:
- In addition to the
codata
data frame, this release includescodata.cor
, a correlation matrix for all the constants. - In addition to
syms_with_errors
andsyms_with_units
, there is a new list of symbols calledsyms_with_quantities
(available if the optionalquantities
package is installed), which provides constant values with uncertainty and units. - Experimental support for correlated values in
syms_with_errors
andsyms_with_quantities
is provided (disabled by default; see details inhelp(syms)
for activation instructions).
constants 0.0.2
CRAN release: 2018-01-08
- Use
units::as_units()
instead of the deprecatedunits::parse_unit()
(#1). - Install the speed of light as a unit (#2).
- Unitless constants now show a
1
instead ofunitless
as unit (#3). - Unit
Ω
has been replaced byohm
(#4).