make.unique {base} | R Documentation |
Makes the elements of a character vector unique by appending sequence numbers to duplicates.
make.unique(names, sep = ".")
names |
a character vector |
sep |
a character string used to separate a duplicate name from its sequence number. |
The algorithm used by make.unique
has the property that
make.unique(c(A, B)) == make.unique(c(make.unique(A), B))
.
In other words, you can append one string at a time to a vector,
making it unique each time, and get the same result as applying
make.unique
to all of the strings at once.
If character vector A
is already unique, then
make.unique(c(A, B))
preserves A
.
A character vector of same length as names
with duplicates changed.
Thomas P Minka
make.unique(c("a", "a", "a")) make.unique(c(make.unique(c("a", "a")), "a")) make.unique(c("a", "a", "a.2", "a")) make.unique(c(make.unique(c("a", "a")), "a.2", "a")) rbind(data.frame(x=1), data.frame(x=2), data.frame(x=3)) rbind(rbind(data.frame(x=1), data.frame(x=2)), data.frame(x=3))