I have a large data set with city names. Many of the names are not consistent.
Example:
vec = c("New York", "New York City", "new York CIty", "NY", "Berlin", "BERLIn", "BERLIN", "London", "LONDEN", "Lond", "LONDON")
I want to use fuzzywuzzyR
to bring them into a consistent format. The problem is I a have no master list of the original city names.
This package provides the possibility to detect duplicates like this:
library(fuzzywuzzyR)
init_proc = FuzzUtils$new()
PROC = init_proc$Full_process
init_scor = FuzzMatcher$new()
SCOR = init_scor$WRATIO
init = FuzzExtract$new()
init$Dedupe(contains_dupes = vec, threshold = 70L, scorer = SCOR)
dict_keys(['New York City', 'NY', 'BERLIN', 'LONDEN'])
Or I can set a "master value" like this:
master = "London"
init$Extract(string = master, sequence_strings = vec, processor = PROC, scorer = SCOR)
[[1]]
[[1]][[1]]
[1] "London"
[[1]][[2]]
[1] 100
[[2]]
[[2]][[1]]
[1] "LONDON"
[[2]][[2]]
[1] 100
[[3]]
[[3]][[1]]
[1] "Lond"
[[3]][[2]]
[1] 90
[[4]]
[[4]][[1]]
[1] "LONDEN"
[[4]][[2]]
[1] 83
[[5]]
[[5]][[1]]
[1] "NY"
[[5]][[2]]
[1] 45
My question is how can I use this to replace all matches in the list with the same value i.e. I would like to replace all values that match the master value with "London". However, I don´t have the master values. So, I need to have a list of matches and replace the values. In this case it would be "New York", "London" "Berlin". After the process, vec
should looklike this.
new_vec = c("New York", "New York", "New York", "New York", "Berlin", "Berlin", "Berlin", "London", "London", "London", "London")
Update
@camille came up with the idea of using world.cities
of the maps
package. I found this post using fuzzyjoin
dealing with a similar problem.
To use this I convert vec
to a data frame.
vec = as.data.frame(vec, stringsAsFactors = F)
colnames(vec) = c("City")
Then using the fuzzyjoin
package together with world.cities
of the maps
package.
library(maps)
library(fuzzyjoin)
vec %>%
stringdist_left_join(world.cities, by = c(City = "name"), distance_col = "d") %>%
group_by(City) %>%
top_n(1)
The output looks like this:
# A tibble: 50 x 3
# Groups: City [5]
City name d
<chr> <chr> <dbl>
1 New York New York 0
2 NY Ae 2
3 NY Al 2
4 NY As 2
5 NY As 2
6 NY As 2
7 NY Au 2
8 NY Ba 2
9 NY Bo 2
10 NY Bo 2
# ... with 40 more rows
The Problem is that I have no Idea how to use the distance between ´nameand
City` to change the misspelled values into the right ones for all cities. In theory the corret value must be the closest one. But i.e. for NY this not the case.