stri_sub_all: Extract or Replace Multiple Substrings

Description

stri_sub_all extracts multiple substrings from each string. Its replacement version substitutes (in-place) multiple substrings with the corresponding replacement strings. stri_sub_replace_all (alias stri_sub_all_replace) is magrittr's pipe-operator-friendly variant, returning a copy of the input vector.

For extracting/replacing single substrings from/within each string, see stri_sub.

Usage

stri_sub_all(str, from = list(1L), to = list(-1L), length)
stri_sub_all(str, from=list(1L), to=list(-1L), length, omit_na=FALSE) <- value
stri_sub_replace_all(..., replacement, value = replacement)
stri_sub_all_replace(..., replacement, value = replacement)

Arguments

str

a character vector

from

a list of integer vectors giving the start indexes or a list of two-column matrices, each of type cbind(from, to)

a list of integer vectors giving the end indexes

length

a list of integer vectors giving the substring lengths

omit_na

a single logical value; indicates whether missing values in any of the indexes or in value leave the part of the corresponding input string unchanged [replacement function only]

value

a list of character vectors defining the replacement strings [replacement function only]

...

arguments to be passed to stri_sub_all<-

replacement

alias of value [wherever applicable]

Value

stri_sub_all returns a list of character vectors. Its replacement versions return a character vector.

Details

Vectorized over str, [value], from and (to or length). Just like in stri_sub, parameters to and length are mutually exclusive.

In one of the simplest scenarios, stri_sub_all(str, from, to), the i-th element of the resulting list is generated by calling, e.g., stri_sub(str[i], from[[i]], to[[i]]). As usual, if one of the inputs is of length smaller than the others, recycling rule is applied.

If any of from, to, length, or value is not a list, it is wrapped into a list.

from can be a list of two-column matrices. In such a case, the two columns play a role of from and to, respectively. Such types of index matrices are generated by stri_locate_all. If extraction or replacement based on stri_locate_first or stri_locate_last is needed, see stri_sub.

In the replacement function, the index ranges must be sorted with respect to from are must be mutually disjoint.

Examples

Run this code

# NOT RUN {
x <- c('12 3456 789', 'abc', '', NA, '667')
stri_sub_all(x, stri_locate_all_regex(x, '[0-9]+')) # see stri_extract_all
stri_sub_all(x, stri_locate_all_regex(x, '[0-9]+', omit_no_match=TRUE))

stri_sub_all(x, stri_locate_all_regex(x, '[0-9]+', omit_no_match=TRUE)) <- '***'
print(x)

stri_sub_replace_all('a b c', c(1, 3, 5), c(1, 3, 5), replacement=c('A', 'B', 'C'))


# }

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