Superseded helper for lumping factor levels

fct_lump() automatically chooses between fct_lump_min(), fct_lump_prop(), fct_lump_n(), and fct_lump_lowfreq() based on its arguments. It is kept for backward compatibility, but is superseded and no longer recommended for new code.

For new code, prefer the more explicit helpers: fct_lump_min(), fct_lump_prop(), fct_lump_n(), and fct_lump_lowfreq().

Usage

fct_lump(
  f,
  n,
  prop,
  w = NULL,
  other_level = "Other",
  ties.method = c("min", "average", "first", "last", "random", "max")
)

Arguments

f

A factor (or character vector).

n

Positive n preserves the most common n values. Negative n preserves the least common -n values. If there are ties, you will get at least abs(n) values.

prop

Positive prop lumps values which do not appear at least prop of the time. Negative prop lumps values that do not appear at most -prop of the time.

w

An optional numeric vector giving weights for frequency of each value (not level) in f.

other_level

Value of level used for "other" values. Always placed at end of levels.

ties.method

A character string specifying how ties are treated. See rank() for details.

Examples

x <- factor(letters[rpois(100, 5)])
table(x)
#> x
#>  a  b  c  d  e  f  g  h  i 
#>  1  9 13 24 13 18 12  8  2 
table(fct_lump(x, n = 3))
#> 
#>     c     d     e     f Other 
#>    13    24    13    18    32