On 26-Sep-2013 07:55:38 Rolf Turner wrote: > On 09/26/13 19:31, Babak Bastan wrote: >> Hi experts, >> >> If I test sin(pi) in r, it returns me 1.224606e-16 >> >> Why doesn't return me 0? > > If you think that 1.224606e-16 is different from 0, you should probably not > be using computers.
Is that a Fortune? And, if so, should R be using computers? sin(pi) # [1] 1.224606e-16 sin(pi)==0 # [1] FALSE > See FAQ 7.31 (which is in a way about the inverse of > your question, but it should provide the necessary insight). > > cheers, > Rolf Turner Though, mind you, FAQ 3.71 does also offer some consolation to R: all.equal(0,sin(pi)) # [1] TRUE So it depends on what you mean by "different from". Computers have their own fuzzy concept of this ... Babak has too fussy a concept. Ted. ------------------------------------------------- E-Mail: (Ted Harding) <ted.hard...@wlandres.net> Date: 26-Sep-2013 Time: 09:13:33 This message was sent by XFMail ______________________________________________ R-help@r-project.org 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.
