compareVersion {utils} | R Documentation

## Compare Two Package Version Numbers

### Description

Compare two package version numbers to see which is later.

### Usage

    compareVersion(a, b)

### Arguments

`a, b` | Character strings representing package version numbers.

### Details

R package version numbers are of the form `x.y-z` for integers `x`, `y` and `z`, with components after `x` optionally missing (in which case the version number is older than those with the components present).

### Value

`0` if the numbers are equal, `-1` if `b` is later and `1` if `a` is later (analogous to the C function `strcmp`).

### See Also

`package_version`, `library`, `packageStatus`.

### Examples

    compareVersion("1.0", "1.0-1")
    compareVersion("7.2-0","7.1-12")

[Package utils version 2.15.1 Index]