On 01/22/2016 10:46 AM, li li wrote:
Hi all,
I encountered the following strange phenomenon.
For some reason, the obs_p[1] and res1$st_p[89] have
the same value but when I run "==", it returns FALSE.
Can anyone help give some explanation on this?
Thanks very much!
Hanna
obs_p[1]
[1] 0.002201438
res1$st_p[89]
[1] 0.002201438
res1$st_p[89]==obs_p[1]
[1] FALSE
res1$st_p[89]<obs_p[1]
[1] FALSE
res1$st_p[89]>obs_p[1]
[1] TRUE
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
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I believe the decimal representation is only approximate. The real
internal values in binary are different. If you want to have comparisons
like this result in being considered equal, I think there is a way to
use a fuzzy comparison but I don't remember the details.
Rick
--
Richard A. Bilonick, PhD
Assistant Professor
Dept. of Ophthalmology, School of Medicine
Dept. of Biostatistics, Graduate School of Public Health
Dept. of Orthodontics, School of Dental Medicine
University of Pittsburgh
Principal Investigator for the Pittsburgh Aerosol Research
and Inhalation Epidemiology Study (PARIES)
412 647 5756
______________________________________________
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
