stringdist_join {fuzzyjoin}

Join two tables based on fuzzy string matching of their columns

Description

Join two tables based on fuzzy string matching of their columns. This is useful, for example, in matching free-form inputs in a survey or online form, where it can catch misspellings and small personal changes.

Usage

stringdist_join(
  x,
  y,
  by = NULL,
  max_dist = 2,
  method = c("osa", "lv", "dl", "hamming", "lcs", "qgram", "cosine", "jaccard", "jw",
    "soundex"),
  mode = "inner",
  ignore_case = FALSE,
  distance_col = NULL,
  ...
)

stringdist_inner_join(x, y, by = NULL, distance_col = NULL, ...)

stringdist_left_join(x, y, by = NULL, distance_col = NULL, ...)

stringdist_right_join(x, y, by = NULL, distance_col = NULL, ...)

stringdist_full_join(x, y, by = NULL, distance_col = NULL, ...)

stringdist_semi_join(x, y, by = NULL, distance_col = NULL, ...)

stringdist_anti_join(x, y, by = NULL, distance_col = NULL, ...)

Arguments

x

A tbl

y

A tbl

by

Columns by which to join the two tables

max_dist

Maximum distance to use for joining

method

Method for computing string distance, see stringdist-metrics in the stringdist package.

mode

One of "inner", "left", "right", "full" "semi", or "anti"

ignore_case

Whether to be case insensitive (default yes)

distance_col

If given, will add a column with this name containing the difference between the two

...

Arguments passed on to stringdist

Details

If method = "soundex", the max_dist is automatically set to 0.5, since soundex returns either a 0 (match) or a 1 (no match).

Examples

library(dplyr)
library(ggplot2)
data(diamonds)

d <- data_frame(approximate_name = c("Idea", "Premiums", "Premioom",
                                     "VeryGood", "VeryGood", "Faiir"),
                type = 1:6)

# no matches when they are inner-joined:
diamonds %>%
  inner_join(d, by = c(cut = "approximate_name"))

# but we can match when they're fuzzy joined
diamonds %>%
 stringdist_inner_join(d, by = c(cut = "approximate_name"))