Hi All, I am using the function fractions() and cognates from MASS. I would like to be able to tell if some calculations I am doing on some rationals are transformed into floats and then retransformed into rationals.
For instance I suspect that as.fractions(1/8) + as.fractions(1/4) does transform into floats and back, while I know 1/as.fractions(8) + 1/as.fractions(4) does not. Since I am using sum() and doing a number of multiplications I would like to know so I can intervene. For instance, what's happening here? > pun [,1] [,2] [1,] 1 1 [2,] 4 4 > library(MASS) > pun[1,]/as.fractions(pun[2,]) [1] 1/4 1/4 > sum(pun[1,]/as.fractions(pun[2,])) [1] 1/2 Best, Federico -- Federico C. F. Calboli Department of Epidemiology and Public Health Imperial College, St. Mary's Campus Norfolk Place, London W2 1PG Tel +44 (0)20 75941602 Fax +44 (0)20 75943193 f.calboli [.a.t] imperial.ac.uk f.calboli [.a.t] gmail.com ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.