[R] Variance for Vector of Constants is Not Zero

[Spencer Graves]

	  Could you please provide "sessionInfo()";  I can't replicate the 
problem:

 > var(x)
[1] 0
 > sessionInfo()
R version 2.2.1, 2005-12-20, i386-pc-mingw32

attached base packages:
[1] "methods"   "stats"     "graphics"  "grDevices" "utils"     "datasets"
[7] "base"

	  spencer graves

Barry Zajdlik wrote:

> Hi All,
> 
> An annoying but not critical problem I am having is that the variance of
> a vector of constants is reported as > 0. I imagine there is a simple
> workaround for the following but could not find it after having spent an
> embarrassing amount of time.
> 
> In Splus:
> 
> 
>>x<-rep(0.02,10)
>>var(x)
>>0
> 
> 
> In R:
> 
> x<-rep(0.02,10)
> var(x)
> 1.337451e-35
> 
> I assumed the problem had to do with machine precision and suitably
> modified .Machine$double.eps and .Machine$double.neg.eps which I thought
> would fix the problem but without success. Any pointers to a solution
> would be appreciated!
> 
> Cheers,
> Barry Zajdlik
> 
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