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base (version 3.3)

numeric_version: Numeric Versions

Description

A simple S3 class for representing numeric versions including package versions, and associated methods.

Usage

numeric_version(x, strict = TRUE) package_version(x, strict = TRUE) R_system_version(x, strict = TRUE) getRversion()

Arguments

x
a character vector with suitable numeric version strings (see ‘Details’); for package_version, alternatively an R version object as obtained by R.version.
strict
a logical indicating whether invalid numeric versions should results in an error (default) or not.

Details

Numeric versions are sequences of one or more non-negative integers, usually (e.g., in package ‘DESCRIPTION’ files) represented as character strings with the elements of the sequence concatenated and separated by single . or - characters. R package versions consist of at least two such integers, an R system version of exactly three (major, minor and patchlevel).

Functions numeric_version, package_version and R_system_version create a representation from such strings (if suitable) which allows for coercion and testing, combination, comparison, summaries (min/max), inclusion in data frames, subscripting, and printing. The classes can hold a vector of such representations.

getRversion returns the version of the running R as an R system version object.

The [[ operator extracts or replaces a single version. To access the integers of a version use two indices: see the examples.

See Also

compareVersion; packageVersion for the version of a specific R package. R.version etc for the version of R (and the information underlying getRversion()).

Examples

Run this code
x <- package_version(c("1.2-4", "1.2-3", "2.1"))
x < "1.4-2.3"
c(min(x), max(x))
x[2, 2]
x$major
x$minor

if(getRversion() <= "2.5.0") { ## work around missing feature
  cat("Your version of R, ", as.character(getRversion()),
      ", is outdated.\n",
      "Now trying to work around that ...\n", sep = "")
}

x[[c(1, 3)]]  # '4' as a numeric vector, same as x[1, 3]
x[1, 3]      # 4 as an integer
x[[2, 3]] <- 0   # zero the patchlevel
x[[c(2, 3)]] <- 0 # same
x
x[[3]] <- "2.2.3"; x
x <- c(x, package_version("0.0"))
is.na(x)[4] <- TRUE
stopifnot(identical(is.na(x), c(rep(FALSE,3), TRUE)),
	  anyNA(x))

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