mvbutils: multirep – R documentation

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multirep

Replacement and insertion functions with more/less than 1 replacement per spot

Description

multirep is like replace, but the replacements are a list of the same length as the number of elements to replace. Each element of the list can have 0, 1, or more elements– the original vector will be expanded/contracted accordingly. (If all elements of the list have length 1, the result will be the same length as the original.) multinsert is similar, but doesn't overwrite the elements in orig (so the result of multinsert is longer). massrep is like multirep, but takes lists as arguments so that a group-of-line-numbers in the first list is replaced by a group-of-lines in the second list.

Usage

multirep( orig, at, repl, sorted.at=TRUE)
multinsert( orig, at, ins, sorted.at=TRUE)
massrep( orig, atlist, replist, sorted.at=TRUE)

Arguments

`orig`	vector
`at`	numeric vector, saying which elements of the original will be replaced or appended-to. Can't exceed `length(orig)`. 0 is legal in `multinsert` but not `multirep`. Assumed sorted unless `sorted.at` is set to FALSE.
`atlist`	list where each element is a group of line numbers to be replaced by the corresponding element of `replist` (and that element can have a different length). Normally each group of line numbers would be consecutive, but this is not mandatory.
`repl, ins, replist`	a list of replacements. `repl[[i]]` will replace line `at[i]` in `orig`, possibly removing it (if `repl[[i]]` has length 0) or inserting extra elements (if `repl[[i]]` has length > 1). In `multinsert`, `repl` can be a non-list, whereupon it will be cast to `list(repl)` [if `at` is length 1] or `as.list(repl)` [if `at` is length>1]. If `length(repl`) < `length(at)`, `repl` will be replicated to the appropriate size. If `repl` is atomic, it will be typecast into a list– in this case, all replacements/insertions will be of length 1.
`sorted.at`	if TRUE, then `at` had better be sorted beforehand; if FALSE, `at` will be sorted for you inside `multirep`, and `repl` is reordered accordingly.

Examples

multirep( cq( the, cat, sat, on, the, mat), c( 2, 6),
    list( cq( big, bug), cq( elephant, howdah, cushion)))
# [1] "the" "big" "bug" "sat" "on" "the" "elephant" "howdah" "cushion"
multirep( cq( the, cat, sat, on, the, mat), c( 2, 6),
    list( cq( big, bug), character(0)))
# [1] "the" "big" "bug" "sat" "on" "the"
# NB the 0 in next example:
multinsert( cq( cat, sat, on, mat), c( 0, 4),
    list( cq( fat), cq( cleaning, equipment)))
# [1] "fat" "cat" "sat" "on" "mat" "cleaning" "equipment"

mvbutils

Workspace Organization, Code and Documentation Editing, Package Prep and Editing, Etc

v2.8.232

GPL (>= 2)

Authors

Mark V. Bravington <mark.bravington@csiro.au>

Initial release

2018-12-11