Re: [R] bug in difftime with as.POSIXct

From: Dan Kelley <>
Date: Sun, 27 Jan 2008 11:20:26 -0800 (PST)

Oh, I'm sorry to be posting a reply to my own stupid question, but the problem is that I had not specified GMT, and so it was using local time, which changes to 'save daylight". This is demonstrated below:

> unclass(as.POSIXct("1975-04-27",tz="GMT"))[1]-unclass(as.POSIXct("1975-04-28",tz="GMT"))[1]
[1] -86400
> unclass(as.POSIXct("1975-04-27"))[1]-unclass(as.POSIXct("1975-04-28"))[1]
[1] -82800

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Received on Sun 27 Jan 2008 - 19:24:49 GMT

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