PreciseSums: Accurate Floating Point Sums and Products

Most of the time floating point arithmetic does approximately the right thing. When adding sums or having products of numbers that greatly differ in magnitude, the floating point arithmetic may be incorrect. This package implements the Kahan (1965) sum <doi:10.1145/363707.363723>, Neumaier (1974) sum <doi:10.1002/zamm.19740540106>, pairwise-sum (adapted from 'NumPy', See Castaldo (2008) <doi:10.1137/070679946> for a discussion of accuracy), and arbitrary precision sum (adapted from the fsum in 'Python' ; Shewchuk (1997) <>). In addition, products are changed to long double precision for accuracy, or changed into a log-sum for accuracy.

Version: 0.3
Depends: R (≥ 3.2)
Suggests: testthat
Published: 2018-04-12
Author: Matthew Fidler [aut, cre, cph], Raymond Hettinger [cph, aut], Jonathan Shewchuk [cph, aut], Julian Taylor [cph, aut], Nathaniel Smith [cph, aut], NumPy Team [cph], Python Team [cph]
Maintainer: Matthew Fidler <matthew.fidler at>
License: GPL-2 | GPL-3 [expanded from: GPL (≥ 2)]
NeedsCompilation: yes
CRAN checks: PreciseSums results


Reference manual: PreciseSums.pdf
Package source: PreciseSums_0.3.tar.gz
Windows binaries: r-devel:, r-release:, r-oldrel:
OS X binaries: r-release: PreciseSums_0.3.tgz, r-oldrel: PreciseSums_0.3.tgz
Old sources: PreciseSums archive

Reverse dependencies:

Reverse imports: nlmixr, RxODE
Reverse linking to: RxODE


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