Compare Two Package Version Numbers

Description

Compare two package version numbers to see which is later.

Usage

compareVersion(a, b)

Arguments

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).

Gives an R error on malformed inputs.

See Also

package_version, library, packageStatus.

Examples

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