locate: Locate all occurrences of a vector (needle) within another...
In coolbutuseless/minilocate: Find Needles in Haystacks

Description Usage Arguments Details Value

View source: R/locate.R

This will return all starting locations of the needle found within the haystack - even overlapping ones.

locate(needle, haystack, alignment = NA_integer_)

cached_locate(needle, haystack, alignment = NA_integer_)

locate_next(needle, haystack, start = 1L, alignment = NA)

`needle`	vector of values
`haystack`	vector of values
`alignment`	search must start at a multiple of this index location (+1). Useful for byte-aligned searches of bit vectors i.e. `alignment=8`. Default: NA (no alignment).
`start`	lowest index to accept

The routine is pretty relaxed about types so you can search for an integer vector within a character vector if you so choose.

Supported types:

all built-in atomic types in R i.e. integer, numeric, real, character, complex, raw
bit type from the bit package - Note: in order to search for the matches, 'bit' objects are basically extracted to their equivalent logical vector causing higher memory usage and negating any memory savings of using 'bit'.

locate is the core location function. There is no cacheing, so identical searches are started from scratch each time.

cached_locate is a memoised version of locate. Because calling locate can be quite an expensive operation, searches for a given sequence in a haystack are cached to save time on subsequent calls.

locate_next gives the first index on, or after, the given start index.

Adapted from code originally written by carroll_jono - https://twitter.com/carroll_jono

Indices of the start of all occurrences of needle in haystack, or NA if no matches found.

coolbutuseless/minilocate documentation built on May 20, 2019, 9:41 a.m.