rational solution in R [Software]

posted by mittyri – Russia, 2020-12-21 13:49 (74 d 15:57 ago) – Posting: # 22152
Views: 1,255

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:

Activity
 Admin contact
21,370 posts in 4,463 threads, 1,495 registered users;
online 9 (0 registered, 9 guests [including 2 identified bots]).
Forum time: Saturday 05:46 CET (Europe/Vienna)

If debugging is the process of removing bugs,
then programming must be the process of putting them in.    Edsger W. Dijkstra

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz
HTML5