,
Thibaut Jombart [ctb],
Patrick Barks [ctb]| Title: | Flexible Dictionary-Based Cleaning |
|---|---|
| Description: | Provides flexible dictionary-based cleaning that allows users to specify implicit and explicit missing data, regular expressions for both data and columns, and global matches, while respecting ordering of factors. This package is part of the 'RECON' (<https://www.repidemicsconsortium.org/>) toolkit for outbreak analysis. |
| Authors: | Zhian N. Kamvar [aut, cre] ,
Thibaut Jombart [ctb],
Patrick Barks [ctb] |
| Maintainer: | Zhian N. Kamvar <[email protected]> |
| License: | GPL-3 |
| Version: | 0.1.1 |
| Built: | 2024-11-26 03:05:47 UTC |
| Source: | https://github.com/reconhub/matchmaker |
This function allows you to clean your data according to pre-defined rules encapsulated in either a data frame or list of data frames. It has application for addressing mis-spellings and recoding variables (e.g. from electronic survey data).
match_df( x = data.frame(), dictionary = list(), from = 1, to = 2, by = 3, order = NULL, warn = FALSE )match_df( x = data.frame(), dictionary = list(), from = 1, to = 2, by = 3, order = NULL, warn = FALSE )
x |
a character or factor vector |
dictionary |
a data frame or named list of data frames with at least two
columns defining the word list to be used. If this is a data frame, a third
column must be present to split the dictionary by column in |
from |
a column name or position defining words or keys to be replaced |
to |
a column name or position defining replacement values |
by |
character or integer. If |
order |
a character the column to be used for sorting the values in each data frame. If the incoming variables are factors, this determines how the resulting factors will be sorted. |
warn |
if |
By default, this applies the function match_vec() to all
columns specified by the column names listed in by, or, if a
global dictionary is used, this includes all character and factor
columns as well.
by columnSpelling variables within dictionary represent keys that you want to match
to column names in x (the data set). These are expected to match exactly
with the exception of two reserved keywords that starts with a full stop:
.regex [pattern]: any column whose name is matched by [pattern]. The
[pattern] should be an unquoted, valid, PERL-flavored regular expression.
.global: any column (see Section Global dictionary)
A global dictionary is a set of definitions applied to all valid columns of
x indiscriminantly.
.global keyword in by: If you want to apply a set of definitions to
all valid columns in addition to specified columns, then you can include a
.global group in the by column of your dictionary data frame. This is
useful for setting up a dictionary of common spelling errors. NOTE:
specific variable definitions will override global defintions. For
example: if you have a column for cardinal directions and a definiton for
N = North, then the global variable N = no will not override that. See
Example.
by = NULL: If you want your data frame to be applied to
all character/factor columns indiscriminantly, then setting
by = NULL will use that dictionary globally.
a data frame with re-defined data based on the dictionary
Zhian N. Kamvar
Patrick Barks
match_vec(), which this function wraps.
# Read in dictionary and coded date examples -------------------- dict <- read.csv(matchmaker_example("spelling-dictionary.csv"), stringsAsFactors = FALSE) dat <- read.csv(matchmaker_example("coded-data.csv"), stringsAsFactors = FALSE) dat$date <- as.Date(dat$date) # Clean spelling based on dictionary ----------------------------- dict # show the dict head(dat) # show the data res1 <- match_df(dat, dictionary = dict, from = "options", to = "values", by = "grp") head(res1) # Show warnings/errors from each column -------------------------- # Internally, the `match_vec()` function can be quite noisy with warnings for # various reasons. Thus, by default, the `match_df()` function will keep # these quiet, but you can have them printed to your console if you use the # warn = TRUE option: res1 <- match_df(dat, dictionary = dict, from = "options", to = "values", by = "grp", warn = TRUE) head(res1) # You can ensure the order of the factors are correct by specifying # a column that defines order. dat[] <- lapply(dat, as.factor) as.list(head(dat)) res2 <- match_df(dat, dictionary = dict, from = "options", to = "values", by = "grp", order = "orders") head(res2) as.list(head(res2))# Read in dictionary and coded date examples -------------------- dict <- read.csv(matchmaker_example("spelling-dictionary.csv"), stringsAsFactors = FALSE) dat <- read.csv(matchmaker_example("coded-data.csv"), stringsAsFactors = FALSE) dat$date <- as.Date(dat$date) # Clean spelling based on dictionary ----------------------------- dict # show the dict head(dat) # show the data res1 <- match_df(dat, dictionary = dict, from = "options", to = "values", by = "grp") head(res1) # Show warnings/errors from each column -------------------------- # Internally, the `match_vec()` function can be quite noisy with warnings for # various reasons. Thus, by default, the `match_df()` function will keep # these quiet, but you can have them printed to your console if you use the # warn = TRUE option: res1 <- match_df(dat, dictionary = dict, from = "options", to = "values", by = "grp", warn = TRUE) head(res1) # You can ensure the order of the factors are correct by specifying # a column that defines order. dat[] <- lapply(dat, as.factor) as.list(head(dat)) res2 <- match_df(dat, dictionary = dict, from = "options", to = "values", by = "grp", order = "orders") head(res2) as.list(head(res2))
This function provides an interface for forcats::fct_recode(),
forcats::fct_explicit_na(), and forcats::fct_relevel() in such a way that
a data dictionary can be imported from a data frame.
match_vec( x = character(), dictionary = data.frame(), from = 1, to = 2, quiet = FALSE, warn_default = TRUE, anchor_regex = TRUE )match_vec( x = character(), dictionary = data.frame(), from = 1, to = 2, quiet = FALSE, warn_default = TRUE, anchor_regex = TRUE )
x |
a character or factor vector |
dictionary |
a matrix or data frame defining mis-spelled words or keys
in one column ( |
from |
a column name or position defining words or keys to be replaced |
to |
a column name or position defining replacement values |
quiet |
a |
warn_default |
a |
anchor_regex |
a |
from column)The from column of the dictionary will contain the keys that you want to
match in your current data set. These are expected to match exactly with
the exception of three reserved keywords that start with a full stop:
.regex [pattern]: will replace anything matching [pattern]. This
is executed before any other replacements are made. The [pattern]
should be an unquoted, valid, PERL-flavored regular expression. Any
whitespace padding the regular expression is discarded.
.missing: replaces any missing values (see NOTE)
.default: replaces ALL values that are not defined in the dictionary
and are not missing.
to column)The values will replace their respective keys exactly as they are presented.
There is currently one recognised keyword that can be placed in the to
column of your dictionary:
.na: Replace keys with missing data. When used in combination with the
.missing keyword (in column 1), it can allow you to differentiate
between explicit and implicit missing data.
a vector of the same type as x with mis-spelled labels cleaned.
Note that factors will be arranged by the order presented in the data
dictionary; other levels will appear afterwards.
If there are any missing values in the from column (keys), then they
are automatically converted to the character "NA" with a warning. If you want
to target missing data with your dictionary, use the .missing keyword. The
.regex keyword uses gsub() with the perl = TRUE option for replacement.
Zhian N. Kamvar
match_df() for an implementation that acts across
multiple variables in a data frame.
corrections <- data.frame( bad = c("foubar", "foobr", "fubar", "unknown", ".missing"), good = c("foobar", "foobar", "foobar", ".na", "missing"), stringsAsFactors = FALSE ) corrections # create some fake data my_data <- c(letters[1:5], sample(corrections$bad[-5], 10, replace = TRUE)) my_data[sample(6:15, 2)] <- NA # with missing elements match_vec(my_data, corrections) # You can use regular expressions to simplify your list corrections <- data.frame( bad = c(".regex f[ou][^m].+?r$", "unknown", ".missing"), good = c("foobar", ".na", "missing"), stringsAsFactors = FALSE ) # You can also set a default value corrections_with_default <- rbind(corrections, c(bad = ".default", good = "unknown")) corrections_with_default # a warning will be issued about the data that were converted match_vec(my_data, corrections_with_default) # use the warn_default = FALSE, if you are absolutely sure you don't want it. match_vec(my_data, corrections_with_default, warn_default = FALSE) # The function will give you a warning if the dictionary does not # match the data match_vec(letters, corrections) # The can be used for translating survey output words <- data.frame( option_code = c(".regex ^[yY][eE]?[sS]?", ".regex ^[nN][oO]?", ".regex ^[uU][nN]?[kK]?", ".missing"), option_name = c("Yes", "No", ".na", "Missing"), stringsAsFactors = FALSE ) match_vec(c("Y", "Y", NA, "No", "U", "UNK", "N"), words)corrections <- data.frame( bad = c("foubar", "foobr", "fubar", "unknown", ".missing"), good = c("foobar", "foobar", "foobar", ".na", "missing"), stringsAsFactors = FALSE ) corrections # create some fake data my_data <- c(letters[1:5], sample(corrections$bad[-5], 10, replace = TRUE)) my_data[sample(6:15, 2)] <- NA # with missing elements match_vec(my_data, corrections) # You can use regular expressions to simplify your list corrections <- data.frame( bad = c(".regex f[ou][^m].+?r$", "unknown", ".missing"), good = c("foobar", ".na", "missing"), stringsAsFactors = FALSE ) # You can also set a default value corrections_with_default <- rbind(corrections, c(bad = ".default", good = "unknown")) corrections_with_default # a warning will be issued about the data that were converted match_vec(my_data, corrections_with_default) # use the warn_default = FALSE, if you are absolutely sure you don't want it. match_vec(my_data, corrections_with_default, warn_default = FALSE) # The function will give you a warning if the dictionary does not # match the data match_vec(letters, corrections) # The can be used for translating survey output words <- data.frame( option_code = c(".regex ^[yY][eE]?[sS]?", ".regex ^[nN][oO]?", ".regex ^[uU][nN]?[kK]?", ".missing"), option_name = c("Yes", "No", ".na", "Missing"), stringsAsFactors = FALSE ) match_vec(c("Y", "Y", NA, "No", "U", "UNK", "N"), words)
show the path to a matchmaker example file
matchmaker_example(name = NULL)matchmaker_example(name = NULL)
name |
the name of a matchmaker example file |
a path to a matchmaker example file
Zhian N. Kamvar
matchmaker_example() # list all of the example files # read in example spelling dictionary sd <- matchmaker_example("spelling-dictionary.csv") read.csv(sd, stringsAsFactors = FALSE) # read in example coded data coded_data <- matchmaker_example("coded-data.csv") coded_data <- read.csv(coded_data, stringsAsFactors = FALSE) str(coded_data) coded_data$date <- as.Date(coded_data$date)matchmaker_example() # list all of the example files # read in example spelling dictionary sd <- matchmaker_example("spelling-dictionary.csv") read.csv(sd, stringsAsFactors = FALSE) # read in example coded data coded_data <- matchmaker_example("coded-data.csv") coded_data <- read.csv(coded_data, stringsAsFactors = FALSE) str(coded_data) coded_data$date <- as.Date(coded_data$date)