datetime - rounding times to the nearest hour in R -

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this question has answer here:

i have data in format

time <-  c("16:53", "10:57", "11:58")

etc

i create new column each of these times rounded nearest hour. cannot seem posix command work me.

as.character(format(data2$time, "%h:%m"))

error in format.default(structure(as.character(x), names = names(x), dim = dim(x), : invalid 'trim' argument

let alone use round command. can advise?

## example times x <- c("16:53", "10:57", "11:58")  ## posix*t objects need both date , time specified ## here, particular date doesn't matter -- there one. tt <- strptime(paste("2001-01-01", x), format="%y-%m-%d %h:%m")  ## use round.date round, format format format(round(tt, units="hours"), format="%h:%m") # [1] "17:00" "11:00" "12:00"

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