funique is a substantially faster alternative to unique. It is generic with a default vector method and a data frame method.
funique(x, …)# S3 method for default
funique(x, sort = FALSE, method = c("auto", "radix", "hash"), …)
# S3 method for data.frame
funique(x, cols = NULL, sort = FALSE, …)
a atomic vector or data frame / list of equal-length columns.
logical. TRUE orders the unique elements / rows. FALSE returns unique values in order of first occurrence, however numeric values are only provided in order of first occurrence when method = "hash" i.e. the radix method always sorts numeric data.
an integer or character string specifying the method of computation:
| Int. | String | Description | ||
| 1 | "auto" | automatic selection: hash for character, logical or if length(x) < 500, else radix. |
||
| 2 | "radix" | use radix ordering to determine unique values. | ||
| 3 | "hash" | use index hashing to determine unique values. |
compute unique rows according to a subset of columns. Columns can be selected using column names, indices, a logical vector or a selector function (i.e. is.character). Note: All columns are returned.
arguments passed to radixorderv, e.g. decreasing or na.last. Only applicable in funique.default if method = "radix".
x with duplicate elements/rows removed.
If x is a data frame / list and all rows are already unique, then x is returned. Otherwise a copy of x with duplicate rows removed is returned. See qF for some additional computational details.
# NOT RUN {
funique(mtcars$cyl)
funique(gv(mtcars, c(2,8,9)))
funique(mtcars, cols = c(2,8,9))
# }
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