Math.Date
Math Group Method for Date/Time Objects

### Description

The math group method for Date, POSIXt, and difftime objects.

### Usage

    ## S3 method for class 'Date':
    round(x, ...)
    ## S3 method for class 'Date':
    trunc(x, ...)
    ## S3 method for class 'POSIXt':
    round(x, units = c("secs", "mins", "hours", "days"))
    ## S3 method for class 'POSIXt':
    trunc(x, units = c("secs", "mins", "hours", "days"),
       ...)
    ## round, trunc, abs, ceiling, floor, sign, signif
    ## S3 method for class 'difftime':
    Math(x, ...)

### Arguments

x | a Date, POSIXt, or difftime object.
units | the unit to truncate or round to.
... | additional arguments.

Value
returns an object of class Date, POSIXt, or difftime.
Differences between Spotfire Enterprise Runtime for R and Open-source R
Tests using the trunc.POSIXt(x, units = "secs") in open-source R appear to demonstrate problems with dates after 2038-01-18 19:14:06.
For example:
R> pct <- as.POSIXct(c("2038-01-18 19:14:06.5", "2038-01-18 19:14:07.5")) R> trunc(pct, "secs") [1] "2038-01-18 19:14:06 PST" "2038-01-18 19:14:08 PST" TERR> pct <- as.POSIXct(c("2038-01-18 19:14:06.5", "2038-01-18 19:14:07.5")) TERR> trunc(pct, "secs") {[1] "2038-01-18 19:14:06 PST" "2038-01-18 19:14:07 PST"}
See Also
Math, Date, POSIXt, difftime, Ops.Date, Summary.Date
Examples

    ## Date
    dput(d <- as.Date("2038-01-19") + 0.9)
    dput(trunc(d))
    dput(round(d))
    ## POSIXt
    pct <- as.POSIXct("2038-01-19 13:34:37.5")
    trunc(pct, "days"); trunc(pct, "hours"); trunc(pct, "mins");
       trunc(pct, "secs")
    round(pct, "days"); round(pct, "hours");
       round(pct, "mins"); round(pct, "secs")
    ## difftime
    dt <- as.difftime("13:34:37.5")
    trunc(dt); floor(dt)
    round(dt); ceiling(dt)
    abs(dt); sign(dt); signif(dt)

Package base version 6.1.5-18
Package Index