Locate the best instance of pattern in the text near loc using the
Bitap algorithm.Returns -1 if no match found. Assumes R's typical 1-based indexing for loc
and the returned value.
This algorithm makes use of the match_distance and match_threshold options to determine
the match. If these values are not set explicitly via the threshold and distance arguments -
their value will use the currently set global option value.
Candidate matches are scored based on: a) the number of spelling differences between the pattern and the text and b) the distance between the candidate match and the expected location.
The match_distance option determines the relative importance of these two metrics.
match_find(text, pattern, loc = 1L, threshold = NULL, distance = NULL)
| text | The text to search. |
|---|---|
| pattern | The pattern to search for. |
| loc | The expected location of the pattern. |
| threshold | Threshold for determining a match (0 - perfect match, 1 - very loose). |
| distance | Distance from expected location scaling for score penalty. |
Index of best match or -1 for no match.
x = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum." match_find(x, "Loren Ibsen")#> [1] 1match_find(x, "Loren Ibsen", threshold = 0.1)#> [1] -1match_find(x, "minimum")#> [1] 137match_find(x, "minimum", threshold = 0.4)#> [1] -1