trunc.POSIXt {Hmisc}R Documentation

return the floor, ceiling, or rounded value of date or time to specified unit.

Description

trunc.POSIXt returns the date truncated to the specified unit. ceiling.POSIXt returns next ceiling of the date at the unit selected in units. floor.POSIXt trunk.POSIXt by another name. round.POSIXt returns the date or time value rounded to nearest specified unit selected in digits.

Usage

ceil(x, units)
## Default S3 method:
ceil(x, units)
## S3 method for class 'POSIXt':
trunc(x, units = c("secs", "mins", "hours", "days", "months", "years"))
## S3 method for class 'POSIXt':
ceil(x, units = c("secs", "mins", "hours", "days", "months", "years"))
## S3 method for class 'POSIXt':
round(x, digits = c("secs", "mins", "hours", "days", "months", "years"))

Arguments

x date to be floored or ceilinged
units unit to that is is rounded up or down to.
digits same as units but different name to be compatible with round generic.

Value

An object of class POSIXlt.

Author(s)

Charles Dupont

See Also

Date POSIXt POSIXlt

Examples

date <- ISOdate(1832, 7, 12)
ceil(date, units='months')  # '1-8-1832'
trunc(date, units='years')     # '1-1-1832'
round.POSIXt(date, digits='months')    # '1-7-1832'
[Package Hmisc version 3.3-1 Index]