Compare Two Package Version Numbers
Compare two package version numbers to see which is later.
- a, b
Character strings representing package version numbers.
R package version numbers are of the form
x.y-z for integers
z, with components after
optionally missing (in which case the version number is older than
those with the components present).
0 if the numbers are equal,
b is later
a is later (analogous to the C function
compareVersion("1.0", "1.0-1") compareVersion("7.2-0","7.1-12")