On 03/03/08 12:52, Xuejun Qin wrote: > Hi, there, > I cannot get accurate value for calculation. > for example: > ld<-sqrt(1*0.05*0.95*0.05*0.95) > 0.05*0.95-ld=-6.938894e-18 > 0.05*0.95-ld==0 is False. > > I met this problem in my program, how can I handle it. Thanks.
I think what you are experiencing is this: http://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f (R FAQ "7.31 Why doesn't R think these numbers are equal?") Maybe handle it using round(). HTH m. ______________________________________________ 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.
