search for: bigq

Hi, has someone experience which routine should be used for creating fractional numbers? The two conversion routines deliver different results > x <- (0:7)/7 > MASS::fractions(x) [1] 0 1/7 2/7 3/7 4/7 5/7 6/7 1 > gmp::as.bigq(x) Big Rational ('bigq') object of length 8: [1] 0 2573485501354569/18014398509481984 2573485501354569/9007199254740992 [4] 7720456504063707/18014398509481984 2573485501354569/4503599627370496 6433713753386423/9007199254740992 [7] 7720456504063707/9007199254740992 1 Following the...

On Sat, 7 Jan 2023 17:29:35 +0100 Sigbert Klinke <sigbert at wiwi.hu-berlin.de> wrote: > > x <- (0:7)/7 > > > MASS::fractions(x) > > [1] 0 1/7 2/7 3/7 4/7 5/7 6/7 1 > > > gmp::as.bigq(x) > > Big Rational ('bigq') object of length 8: > > [1] 0 > 2573485501354569/18014398509481984 2573485501354569/9007199254740992 > > [4] 7720456504063707/18014398509481984 > 2573485501354569/4503599627370496 6433713753386423/9007199254740992 > > [7] 772...

Hi All, is there a function in R that allows me to work with fractions without transforming them to floats (or whatever) in between? Something that would calculate something like: (1/2 + 1/8) * 1/2 = 5/16 without ever transforming to 0.5 and 0.125? Best, Federico -- Federico C. F. Calboli Department of Epidemiology and Public Health Imperial College, St Mary's Campus Norfolk Place,

...R sum does in fact match the result if we use the Kahan algorithm. P. I am glad to see that R sum() is more accurate than the gfortran compiler sum. On 16/03/18 11:37 AM, luke-tierney at uiowa.edu wrote: > Install the gmp package, run your code, and then try this: > > bu <- gmp::as.bigq(u) > bs4 <- bu[1] + bu[2] + bu[3] + bu[4] + bu[5] > s4 <- as.double(bs4) > s1 - s4 > ## [1] 0 > s2[[2]] - s4 > ## [1] 7.105427e-15 > s3 - s4 > ## [1] 7.105427e-15 > identical(s1, s4) > ## [1] TRUE > > `bs4` is the exact sum of the binary rationals in yo...

Hi With package:gmp, is this an expected behavior? > rep(1:3, rep(3, 3)) [1] 1 1 1 2 2 2 3 3 3 > rep(as.bigz(1:3), rep(3, 3)) Big Integer ('bigz') object of length 9: [1] 1 2 3 1 2 3 1 2 3 This code is used inside `outer`, so more worse > outer(1:3, 1:3, `*`) [,1] [,2] [,3] [1,] 1 2 3 [2,] 2 4 6 [3,] 3 6 9 > outer(as.bigz(1:3),

Install the gmp package, run your code, and then try this: bu <- gmp::as.bigq(u) bs4 <- bu[1] + bu[2] + bu[3] + bu[4] + bu[5] s4 <- as.double(bs4) s1 - s4 ## [1] 0 s2[[2]] - s4 ## [1] 7.105427e-15 s3 - s4 ## [1] 7.105427e-15 identical(s1, s4) ## [1] TRUE `bs4` is the exact sum of the binary rationals in your `u` vector; `s4` is the closest double precision to this...

Hi all, I found a discrepancy between the sum() in R and either a sum done in C or Fortran for vector of just 5 elements. The difference is very small, but this is a very small part of a much larger numerical problem in which first and second derivatives are computed numerically. This is part of a numerical method course I am teaching in which I want to compare speeds of R versus Fortran (We

...hrough \code{eval}), \code{numeric} (including \code{INF} and \code{NaN}), \code{complex} (including \code{INF}), \code{matrix}, \code{array}, \code{list}, \code{pairlist}, \code{table}, \code{data.frame}, \code{lm}, \code{randomForest}, \code{randomForest.formula}, \code{ts}, \code{bigz} and \code{bigq} from package \code{gmp}, \code{int64} and \code{uint64} from package \code{int64}, and \code{integer64} from package \code{bit64}. Other classes are processed with \code{as.character( value )}. Table-like structures defines three commands for each structure: \code{nameColumns,} that can be used...