sparse_character: Create sparse character vector

Description

Construction of vectors where only values and positions are recorded. The Length and default values determine all other information.

Usage

sparse_character(values, positions, length, default = "")

Value

sparse character vector

Arguments

values: integer vector, values of non-zero entries.
positions: integer vector, indices of non-zero entries.
length: integer value, Length of vector.
default: integer value, value at indices not specified by positions. Defaults to "". Cannot be NA.

Details

values and positions are expected to be the same length, and are allowed to both have zero length.

Allowed values for value are character values. Missing values such as NA and NA_real_ are allowed as they are turned into NA_character_. Everything else is disallowed. The values are also not allowed to take the same value as default.

positions should be integers or integer-like doubles. Everything else is not allowed. Positions should furthermore be positive (0 not allowed), unique, and in increasing order. Lastly they should all be smaller that length.

For developers:

setting options("sparsevctrs.verbose_materialize" = TRUE) will print a message each time a sparse vector has been forced to materialize.

Examples

Run this code

sparse_character(character(), integer(), 10)

sparse_character(c("A", "C", "E"), c(2, 5, 10), 10)

str(
  sparse_character(c("A", "C", "E"), c(2, 5, 10), 1000000000)
)