Split a vector, list, matrix or dataframe into into a list of matrices or nested list according to substring matches.

subsplit() divides the data in 'x' into groups defined by the presence of shared substrings. If 'x' is a list, the substrings are derived from 'names(x)'. If 'x' is a matrix or data frame, the substrings are instead derived from 'colnames(x)' or, if 'by.row=FALSE', from 'rownames(x)'.

subsplit(
  x,
  by.row = FALSE,
  sep = "\\.|-|_",
  pattern = NULL,
  pos = 1,
  max.nchar = NULL,
  replace = NULL,
  na.rm = TRUE
)

Arguments

x

A character vector, a named list, a matrix or data frame.

by.row

If 'TRUE' and 'x' is a matrix or data frame, the substrings are derived from 'rownames(x)' instead of 'colnames(x)'. Default: FALSE

sep

The pattern to split each element of 'x' by. Default: '\.|-|_'

pattern

The substrings to split by. If 'NULL', substrings will instead be defined from the delimiter 'sep' and position index 'pos' with an internal call to scalop::substri(). Default: NULL

pos

The substring index(es) to be returned. Default: 1

max.nchar

'NULL', or a maximum number of characters that the substrings should be trimmed to contain. Default: NULL

replace

A character vector containing two elements. The first is the pattern to be replaced and the second is the pattern that it will be replaced with. Alternatively, a list of such character vectors, or 'NULL' if no replacement is desired. Default: NULL

na.rm

Remove NA substring positions. Default: TRUE

Value

A list of the same type as 'x' and of length equal to the number of unique substrings found.

See also

str_subset

Examples

if (FALSE) {
Names = c(rep('dog.cat', 5), rep('dog', 2), rep('cat', 2), 'frog')
x.vec = replicate(expr = sample(100, 5), n = 10, simplify = F)
names(x.vec) = Names
subsplit(x.vec, pattern = c('dog', 'cat', 'frog'))
x.mat = replicate(expr = sample(100, 5), n = 10, simplify = T);
colnames(x.mat) = Names
subsplit(x.mat)
subsplit(x.mat, by.row = T)
}