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Ty Canuck

2012-Jan-27 20:45 UTC

[R] date arithmetic discrepancy

What accounts for the different result?
> as.numeric(as.POSIXct("2012-01-13 08:10:00") -
as.POSIXct("2012-01-1300:00:00") , units='secs')
[1] 29400
> trunc(as.numeric(as.POSIXct("2012-01-13 08:10:00") -as.POSIXct("2012-01-13 00:00:00") , units='secs') )
[1] 29399

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Berend Hasselman

2012-Jan-28 06:25 UTC

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[R] date arithmetic discrepancy

On 27-01-2012, at 21:45, Ty Canuck wrote:
> What accounts for the different result?
> 
>> as.numeric(as.POSIXct("2012-01-13 08:10:00") -
as.POSIXct("2012-01-13
> 00:00:00") , units='secs')
> [1] 29400
> 
>> trunc(as.numeric(as.POSIXct("2012-01-13 08:10:00") -
> as.POSIXct("2012-01-13 00:00:00") , units='secs') )
> [1] 29399
See R FAQ 7.31

And try this

d1 <- as.numeric(as.POSIXct("2012-01-13 08:10:00") -
as.POSIXct("2012-01-13 00:00:00") , units='secs')
d2 <- trunc(as.numeric(as.POSIXct("2012-01-13 08:10:00") -
as.POSIXct("2012-01-13 00:00:00") , units='secs') )

sprintf("%.12f",d1)

Berend

R help - Jan 2012 - date arithmetic discrepancy

[R] date arithmetic discrepancy

[R] date arithmetic discrepancy