fuzz_functions {revtools} | R Documentation |
Functions for fuzzy string matching
Description
Duplicate of functions from the Python library 'fuzzywuzzy' (https://github.com/seatgeek/fuzzywuzzy). These functions have been recoded from scratch based on the description given here. For consistency with stringdist
, however, these functions are computed as distances rather than similarities; i.e. low values signify similar strings.
Usage
fuzzdist(a, b, method)
fuzz_m_ratio(a, b)
fuzz_partial_ratio(a, b)
fuzz_token_sort_ratio(a, b)
fuzz_token_set_ratio(a, b)
Arguments
a |
a string |
b |
a vector containing one or more strings |
method |
a function to be called by 'fuzzdist' |
Value
A score of same length as y, giving the proportional dissimilarity between x and y.
Note
fuzz_m_ratio
is a measure of the number of letters that match between two strings. It is calculated as one minus two times the number of matched characters, divided by the number of characters in both strings.
fuzz_partial_ratio
calculates the extent to which one string is a subset of the other. If one string is a perfect subset, then this will be zero.
fuzz_token_sort_ratio
sorts the words in both strings into alphabetical order, and checks their similarity using fuzz_m_ratio
.
fuzz_token_set_ratio
is similar to fuzz_token_sort_ratio
, but compares both sorted strings to
each other, and to a third group made of words common to both strings. It then returns the maximum value of fuzz_m_ratio
from these comparisons.
fuzzdist
is a wrapper function, for compatability with stringdist.
Examples
fuzz_m_ratio("NEW YORK METS", "NEW YORK MEATS")
fuzz_partial_ratio(
"YANKEES",
c("NEW YORK YANKEES", "something else", "YNAKEES")
)
fuzz_token_sort_ratio("New York Mets vs Atlanta Braves", "Atlanta Braves vs New York Melts")
fuzz_token_set_ratio(
a = "mariners vs angels other words",
b = c("los angeles angels of anaheim at seattle mariners", "angeles angels of anaheim ")
)