[R] sprintf() question

[Daniel Nordlund]

> -----Original Message-----
> From: Ted Harding [mailto:Ted.Harding at manchester.ac.uk] 
> Sent: Sunday, May 17, 2009 3:32 PM
> To: Daniel Nordlund
> Cc: r-help at r-project.org
> Subject: RE: [R] sprintf() question
> 
> On 17-May-09 22:03:19, Daniel Nordlund wrote:
> > When I type the following, I get results different from what I
> > expected. 
> > 
> >> sprintf('%a',3)
> > [1] "0x1.8"
> > 
> > Shouldn't the result be
> > 
> > [1] "0x1.8p+2"
> 
> Well, not "p+2" but "p+1"
>   (0x1.8 = 1.1000[2] ; *2 = 11.000[2] = 3[10]) ;
> however, I get:
> 
>   sprintf('%a',3)
>   # [1] "0x1.8p+1"
> 
> which is indeed correct.
> 
>   R version 2.9.0 (2009-04-17) ## Same as yours
>   platform  i486-pc-linux-gnu  ## Different from yours ...
> 
> which perhaps suggests that there may be a mis-compilation in the
> Windows version.
> 
> Ted.
> 
> > I read through the help ?sprintf and didn't find anything 
> that changed
> > my expectation.  What am I misunderstanding?  I am using 
> R-2.9.0 binary
> > from CRAN on Windows XP Pro, and my session info is
> > 
> > 
> >> sessionInfo()
> > R version 2.9.0 (2009-04-17) 
> > i386-pc-mingw32 
> > 
> > locale:
> > LC_COLLATE=English_United States.1252;LC_CTYPE=English_United
> > States.1252;LC_MONETARY=English_United
> > States.1252;LC_NUMERIC=C;LC_TIME=English_United States.1252
> > 
> > attached base packages:
> > [1] stats     graphics  grDevices utils     datasets  
> methods   base   
> >> 
> > 
> > Thanks for any enlightenment.
> > 

Thanks Ted!

Enlightenment is what I asked for, and it is what I got.  I was having a
senior moment I guess.  I was picturing 8 as binary 0100, when obviously it
is binary 1000.  So yes, the required power of 2 is 1, and it is fine with
me that Windows implementation does not display it.  Thanks again.

Dan

Daniel Nordlund
Bothell, WA  USA