Nguyen Dinh Nguyen wrote: > Dear all, > I found something strange when calculating sin of pi value > sin(pi) > [1] 1.224606e-16 > > pi > [1] 3.141593 > > sin(3.141593) > [1] -3.464102e-07 > > Any help and comment should be appreciated. > Regards > Nguyen > Well, sin(pi) is theoretically zero, so you are just seeing zero at two different levels of precision.
The built-in pi has more digits than it displays: > pi [1] 3.141593 > pi - 3.141593 [1] -3.464102e-07 > print(pi, digits=20) [1] 3.141592653589793 > ____________________________ > Nguyen Dinh Nguyen > Garvan Institute of Medical Research > Sydney, Australia > > > ------------------------------------------------------------------------ > > ______________________________________________ > 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. > -- O__ ---- Peter Dalgaard Øster Farimagsgade 5, Entr.B c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 ______________________________________________ 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.
