frank {data.table} | R Documentation |
Similar to base::rank
but much faster. And it accepts vectors, lists, data.frames or data.tables as input. In addition to the ties.method
possibilities provided by base::rank
, it also provides ties.method="dense"
.
bit64::integer64
type is also supported.
frank(x, ..., na.last=TRUE, ties.method=c("average", "first", "random", "max", "min", "dense")) frankv(x, cols=seq_along(x), order=1L, na.last=TRUE, ties.method=c("average", "first", "random", "max", "min", "dense"))
x |
A vector, or list with all it's elements identical in length or data.frame or data.table. |
... |
Only for lists, data.frames and data.tables. The columns to calculate ranks based on. Do not quote column names. If ... is missing, all columns are considered by default. To sort by a column in descending order prefix a "-", e.g., frank(x, a, -b, c). The -b works when b is of type character as well. |
cols |
A character vector of column names (or numbers) of x, to which obtain ranks for. |
order |
An integer vector with only possible values of 1 and -1, corresponding to ascending and descending order. The length of order must be either 1 or equal to that of cols. If length(order) == 1, it's recycled to length(cols). |
na.last |
Control treatment of |
ties.method |
A character string specifying how ties are treated, see |
To be consistent with other data.table
operations, NA
s are considered identical to other NA
s (and NaN
s to other NaN
s), unlike base::rank
. Therefore, for na.last=TRUE
and na.last=FALSE
, NA
s (and NaN
s) are given identical ranks, unlike rank
.
frank
is not limited to vectors. It accepts data.tables (and lists and data.frames) as well. It accepts unquoted column names (with names preceded with a -
sign for descending order, even on character vectors), for e.g., frank(DT, a, -b, c, ties.method="first")
where a,b,c
are columns in DT
. The equivalent in frankv
is the order
argument.
In addition to the ties.method
values possible using base's rank
, it also provides another additional argument "dense" which returns the ranks without any gaps in the ranking. See examples.
A numeric vector of length equal to NROW(x)
(unless na.last = NA
, when missing values are removed). The vector is of integer type unless ties.method = "average"
when it is of double type (irrespective of ties).
# on vectors x = c(4, 1, 4, NA, 1, NA, 4) # NAs are considered identical (unlike base R) # default is average frankv(x) # na.last=TRUE frankv(x, na.last=FALSE) # ties.method = min frankv(x, ties.method="min") # ties.method = dense frankv(x, ties.method="dense") # on data.table DT = data.table(x, y=c(1, 1, 1, 0, NA, 0, 2)) frankv(DT, cols="x") # same as frankv(x) from before frankv(DT, cols="x", na.last="keep") frankv(DT, cols="x", ties.method="dense", na.last=NA) frank(DT, x, ties.method="dense", na.last=NA) # equivalent of above using frank # on both columns frankv(DT, ties.method="first", na.last="keep") frank(DT, ties.method="first", na.last="keep") # equivalent of above using frank # order argument frank(DT, x, -y, ties.method="first") # equivalent of above using frankv frankv(DT, order=c(1L, -1L), ties.method="first")