[R] Log plus one transformation in R

[William Dunlap]

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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