[R] Bug in qnorm or pnorm?

[Trenkler, Dietrich]

> -----Original Message-----
> From:	Trenkler, Dietrich 
> Sent:	Friday, August 06, 2004 3:13 PM
> To:	'r-help'
> Subject:	[R] Bug in qnorm or pnorm?
> 
> I found the following strange behavior  using qnorm() and pnorm():
> 
> > x<-8.21;x-qnorm(pnorm(x))
> [1] 0.0004638484
> > x<-8.22;x-qnorm(pnorm(x))
> [1] 0.01046385
> > x<-8.23;x-qnorm(pnorm(x))
> [1] 0.02046385
> > x<-8.24;x-qnorm(pnorm(x))
> [1] 0.03046385
> > x<-8.25;x-qnorm(pnorm(x))
> [1] 0.04046385
> > x<-8.26;x-qnorm(pnorm(x))
> [1] 0.05046385
> > x<-8.27;x-qnorm(pnorm(x))
> [1] 0.06046385
> > x<-8.28;x-qnorm(pnorm(x))
> [1] 0.07046385
> > x<-8.29;x-qnorm(pnorm(x))
> [1] 0.08046385
> > x<-8.30;x-qnorm(pnorm(x))
> [1] -Inf
> 
> 
> Given that pnorm(8.30) delivers 1 shouldn't we get Inf 
> for  x<-8.30;x-qnorm(pnorm(x)) ?
> 
> Thanks in advance.
> 
	[Dietrich Trenkler]  Oops, forgot to mention:

	> unlist(R.Version())
	         platform              arch                os
system 
	"i386-pc-mingw32"            "i386"         "mingw32"   "i386,
mingw32" 
	           status             major             minor
year 
	               ""               "1"             "9.1"
"2004" 
	            month               day          language 
	             "06"              "21"               "R" 

	D. Trenkler