Log plus one transformation in R
log1p(x), in the base package computes log(1+x) accurately for small x (and large). E.g.,
options(digits=16) base::log1p(1e-14)
[1] 9.99999999999995e-15
base::log1p(1e-14) - base::log(1+1e-14)
[1] 7.992778373591124e-18
as.numeric(log(Rmpfr::mpfr(1,precBits=1000) + Rmpfr::mpfr(1e-14,
precBits=1000))) - log1p(1e-14) [1] 0 Bill Dunlap TIBCO Software wdunlap tibco.com
On Mon, Dec 12, 2016 at 8:23 AM, Faradj Koliev <faradj.g at gmail.com> wrote:
Hi all, How do I perform log(x+1) in R? log1p_trans() from the package ?scales" doesn?t seem to work for me. Best, Faradj
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