[R] POSIX time conversion doesn't display digit

[R_help Help]

Hi,

I have the following string that I converted to a POSIXct:

> a <- "2009-08-24 10:00:00.213"
> a.p <- strptime(a,"%Y-%m-%d %H:%M:%OS")
> as.double(as.POSIXct(a.p))
[1] 1251122400

I can't seem to get the decimal fraction of .213 out by casting to
double or numeric. Is there anyway to make sure that POSIXct spits
that out? Thank you.

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