[R] unixtime conversion

[Prof Brian Ripley]

On Sat, 14 Jul 2007, Patrick Drechsler wrote:

> Hi,
>
> is there an R function to convert unixtime to one of the R time
> formats (using chron or POSIXct)?
>
> Example data:
>
> unixtime       year  month      day     hour
> 1183377301     2007  7          2       13
>
> I would like to only use the first column.

See ?as.POSIXct, especially its examples.  (Isn't that the very obvious 
place to look?)

It seems you want ISOdatetime(1970,1,1,0,0,0) + unixtime

although depending on the 'unix' in 'unixtime' you might have to wrorry 
about leap seconds (which POSIX-compliant systems ignore).

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595