Bioequivalence and Bioavailability Forum • rational solution in R

rational solution in R [Software]

posted by mittyri – Russia, 2020-12-21 14:49 (1580 d 09:13 ago) – Posting: # 22152
Views: 18,160

Hi Helmut,

❝ At least consistently giving not zero. ;-)

❝

library(Rmpfr)

❝ prec <- 64

❝ x <- mpfr(0.5, prec) - mpfr(0.4, prec) - mpfr(0.1, prec)

❝ x

❝ 1 'mpfr' number of precision 64 bits

❝ [1] -2.77555756156289135106e-17

❝ y <- mpfr(-0.4, prec) - mpfr(0.1, prec) + mpfr(0.5, prec)

❝ y

❝ 1 'mpfr' number of precision 64 bits

❝ [1] -2.77555756156289135106e-17

I think the right solution is


install.packages("remotes")

remotes::install_github("bertcarnell/rational")

library(rational)

(rational(5L, 10L) - rational(4L, 10L) - rational(1L, 10L)) == 0

[1] TRUE

Interestingly but I did not find good solution using CRAN

—
Kind regards,
Mittyri

Complete thread:

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