Bioequivalence and Bioavailability Forum • rational solution in R

rational solution in R [Software]

posted by mittyri – Russia, 2020-12-21 14:49 (1387 d 16:35 ago) – Posting: # 22152
Views: 10,492

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:

Spreadsheet failures, any recent examples? ElMaestro 2019-07-18 13:43 [Software]
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        Decidedly off topic Ohlbe 2019-07-19 13:38
        
        OT: R limbo 101 Helmut 2019-07-19 13:00
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        OT: Spreadsheet addiction nobody 2019-07-19 15:53
        
        OT: Spreadsheet addiction Helmut 2019-07-19 19:32
  - Spreadsheet etc. failures zizou 2019-07-20 00:18
    - As designed ☺ Helmut 2019-07-20 02:12
      - As designed ☺ ElMaestro 2019-07-20 09:08
        
        To round or not to round… Helmut 2019-07-20 12:53
        
        To round or not to round… ElMaestro 2019-07-20 19:59
        
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- Spreadsheet failures, any recent examples? Ohlbe 2020-12-10 18:43
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