cleaner
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Fast and Easy Data Cleaning (in R)
% cleaner
cleaner
: Fast and Easy Data Cleaning
Website of this package: https://msberends.github.io/cleaner
The small R package for cleaning and checking data columns in a fast and easy way. Relying on very few dependencies, it provides smart guessing, but with user options to override anything if needed.
It also provides two new data types that are not available in base R: currency
and percentage
.
Contents:
- Why this package
-
How it works
- Cleaning
- Checking
- Speed
- Invalid regular expressions
Why this package
You are probably often served with data that is not clean, not tidy and consequently not ready for analysis at all. For tidying data, there's of course the tidyverse
(https://www.tidyverse.org), which lets you manipulate data in any way you can think of. But for cleaning, our community might still have been lacking a neat solution that makes data cleaning fast and easy with functions that kind of 'think on their own' to do that.
If the CRAN button at the top of this page is green, install the package with:
install.packages("cleaner")
Otherwise, or if you are looking for the latest stable development version, install the package with:
install.packages("remotes") # if you haven't already
remotes::install_github("msberends/cleaner")
How it works
This package provides two types of functions: cleaning and checking.
Cleaning
Use clean()
to clean data. It guesses what kind of data class would best fit your input data. It calls any of the following functions, that can also be used independently. They always return the class from the function name (e.g. clean_Date()
always returns class Date
).
-
clean_logical()
for valuesTRUE
/FALSE
. You only define what should beTRUE
orFALSE
and it handles the rest for you. At default, it supports "Yes" and "No" in the following languages: Arabic, Bengali, Chinese (Mandarin), Dutch, English, French, German, Hindi, Indonesian, Japanese, Malay, Portuguese, Russian, Spanish, Telugu, Turkish and Urdu. This covers at least two-third of the world population (Ulrich Ammon et al., University of Düsseldorf).# English clean_logical(c("Yes", "No", "Invalid", "Unknown")) #> [1] TRUE FALSE NA NA # French clean_logical(c("Oui, c'est ca", "Non, pas encore")) #> [1] TRUE FALSE # Indonesian clean_logical(c("ya :)", "tidak :(")) #> [1] TRUE FALSE
If you define the
true
andfalse
parameters yourself, they will be interpreted as regular expressions:clean_logical(x = c("Positive", "Negative", "Unknown", "Unknown"), true = "pos", false = "neg") #> [1] TRUE FALSE NA NA clean_logical(x = c("Probable", "Not probable"), true = ".*", false = "not") #> [1] TRUE FALSE
-
clean_factor()
for setting and redefining afactor
. You can use regular expressions to match values in your data to set new factor levels.gender_age <- c("male 0-50", "male 50+", "female 0-50", "female 50+") gender_age #> [1] "male 0-50" "male 50+" "female 0-50" "female 50+" clean_factor(gender_age, levels = c("M", "F")) #> [1] M M F F #> Levels: M F clean_factor(gender_age, levels = c("Male", "Female")) #> [1] Male Male Female Female #> Levels: Male Female clean_factor(gender_age, levels = c("0-50", "50+"), ordered = TRUE) #> [1] 0-50 50+ 0-50 50+ #> Levels: 0-50 < 50+
You can also name your levels to let them match your values. They support regular expressions too:
clean_factor(gender_age, levels = c("female" = "Group A", "male 50+" = "Group B", ".*" = "Other")) #> [1] Other Group B Group A Group A #> Levels: Group A Group B Other
-
clean_Date()
for any type of dates. This could be dates imported from Excel, or any combination of days, months and years. For convenience, theformat
parameter understands the date format language of Excel (liked-mmm-yyyy
) and transforms it internally to the human-unreadable POSIX standard that R understands (%e-%b-%Y
):clean_Date("13jul18", "ddmmmyy") #> [1] "2018-07-13" clean_Date("12-06-2012") #> (assuming format 'dd-mm-yyyy') #> [1] "2012-06-12" clean_Date("14 August 2010") #> (assuming format 'dd mmmm yyyy') #> [1] "2010-08-14" clean_Date(38071) #> (assuming Excel format) #> [1] "2004-03-25"
The function to transform
d-mmm-yyyy
to%e-%b-%Y
is available asformat_datetime()
to users. This makes it possible to use it in other date functions too:as.Date("12-13-14", format = format_datetime("mm-yy-dd")) #> [1] "2013-12-14"
-
clean_POSIXct()
to remove all non-date/time characters and transform to a date/time element. It automatically adds the systems timezone, which can be changed by the user:a <- clean_POSIXct("Created log on 2019/04/11 11:23 by user Joe") a #> "2019-04-11 11:23:00 CEST" b <- clean_POSIXct("Log am 2019.04.11 11:23 erstellt", tz = "US/Michigan") b #> "2019-04-11 11:23:00 EDT" difftime(a, b) #> Time difference of -6 hours
-
clean_numeric()
to remove all non-numbers from cluttered input text. It understands usage of dots and comma's in different languages:clean_numeric(c("$ 12,345.67", "€ 12.345,67", "12,345.67", "12345,67")) #> [1] 12345.67 12345.67 12345.67 12345.67 clean_numeric("qwerty123456") #> [1] 123456 clean_numeric("Positive (0.143)") #> [1] 0.143
-
clean_character()
to remove all obvious non-characters from cluttered input text:clean_character("qwerty123456") #> [1] "qwerty" clean_character("Positive (0.143)") #> [1] "Positive"
You can define yourself what should be removed using the
remove
argument, with regular expressions:clean_character(x = c("Model: Pro A1 ", "Model specified: Pro A1", " Pro A1 "), remove = "^.*:") #> [1] "Pro A1" "Pro A1" "Pro A1"
-
clean_percentage()
to use the newpercentage
class that comes with this package. It prints numeric values as percentages usingas.percentage()
:as.percentage(c(0.25, 2.5, 0.025)) #> [1] 25.0% 250.0% 2.5% sum(as.percentage(c(0.25, 2.5, 0.025))) #> [1] 277.5% clean_percentage("PCT: 0.143") #> [1] 14.3%
-
clean_currency()
to use the newcurrency
class that comes with this package. It transforms the input withclean_numeric()
first, after which it will be transformed withas.currency()
, guessing the currency symbol based on your system locale:clean_currency(c("Jack sent £ 25", "Bill sent £ 31.40")) #> [1] `GBP 25.00` `GBP 31.40` received <- clean_currency(c("Received $25", "Received $31.40")) received #> [1] `USD 25.00` `USD 31.40` sum(received) #> [1] `USD 56.40` format(sum(received), currency_symbol = "€", decimal.mark = ",") #> [1] "EUR 56,40"
This new class also comes with support for printing in
tibble
s, used by thetidyverse
:library(dplyr) tibble(money = c("Jack sent £ 25", "Bill sent £ 31.40")) %>% mutate(mutate_cleaner = clean_currency(money)) #> # A tibble: 2 x 2 #> money mutate_cleaner #> <chr> <crncy/GBP> #> 1 Jack sent £ 25 25.00 #> 2 Bill sent £ 31.40 31.40
Other cleaning
-
Use
format_names()
to quickly and easily change names ofdata.frame
columns,list
s orcharacter
vectors.df <- data.frame(old.name = "test1", value = "test2") format_names(df, snake_case = TRUE) format_names(df, camelCase = TRUE) format_names(df, c(old.name = "new_name", value = "measurement")) library(dplyr) starwars %>% format_names(camelCase = TRUE) %>% # changes column names mutate(name = name %>% format_names(snake_case = TRUE)) # changes values in column
-
Use the generic function
na_replace()
to replaceNA
values in any data type. Its default replacement value is dependent on the data type that is given as input:0
for numeric values and classmatrix
,FALSE
for classlogical
, today for classDate
, and""
otherwise.na_replace(c(1, 2, NA, NA)) #> [1] 1 2 0 0 na_replace(c(1, 2, NA, NA), replacement = -1) #> [1] 1 2 -1 -1 na_replace(c(1, 2, NA, NA), replacement = c(0, -1)) #> [1] 1 2 0 -1 na_replace(c("a", "b", NA, NA)) #> [1] "a" "b" "" ""
It also supports replacing
NA
s in complete data sets and supports grouped variables used by thedplyr
package:library(dplyr) starwars %>% na_replace(hair_color) # only replace NAs in this column starwars %>% na_replace() # replace NAs in all columns ("" for hair_color and 0 for birth_year) starwars %>% group_by(hair_color) %>% na_replace(hair_color, replacement = "TEST!") %>% summarise(n = n())
-
Use the function
format_p_value()
to format p values according to the international APA guideline. It tries to round to two decimals, but has a exception for values that would round toalpha
(defaults to 0.05):format_p_value(c(0.345678, 0.123)) #> [1] "0.35" "0.12" # a value of 0.0499 must not be "0.05", but is not "0.049" either, # so the function will add as many decimals as needed: format_p_value(0.04993) #> [1] "0.0499"
Checking
The easiest and most comprehensive way to check the data of a column/variable is to create frequency tables. Use freq()
to do this. It supports a lot of different classes (types of data), weights, and is even extendible by other packages. In markdown documents (like this README file), it formats as real markdown.
freq(unclean$gender)
Frequency table
Class: character
Length: 500
Available: 500 (100%, NA: 0 = 0%)
Unique: 5
Shortest: 1
Longest: 6
Item | Count | Percent | Cum. Count | Cum. Percent | |
---|---|---|---|---|---|
1 | male | 240 | 48.0% | 240 | 48.0% |
2 | female | 220 | 44.0% | 460 | 92.0% |
3 | man | 22 | 4.4% | 482 | 96.4% |
4 | m | 15 | 3.0% | 497 | 99.4% |
5 | F | 3 | 0.6% | 500 | 100.0% |
Clean it and check again (using markdown = FALSE
to show how it would look in the R console):
freq(clean_factor(unclean$gender,
levels = c("^m" = "Male", "^f" = "Female")),
markdown = FALSE)
#> Frequency table
#>
#> Class: factor (numeric)
#> Length: 500
#> Levels: 2: Male, Female
#> Available: 500 (100%, NA: 0 = 0%)
#> Unique: 2
#>
#> Item Count Percent Cum. Count Cum. Percent
#> --- ------- ------ -------- ----------- -------------
#> 1 Male 277 55.4% 277 55.4%
#> 2 Female 223 44.6% 500 100.0%
This could also have been done with dplyr
syntax, since freq()
supports tidy evaluation:
unclean %>%
freq(clean_factor(gender,
levels = c("^m" = "Male", "^f" = "Female")))
# or:
unclean %>%
pull(gender) %>%
clean_factor(c("^m" = "Male", "^f" = "Female")) %>%
freq()
Speed
The cleaning functions are tremendously fast, because they rely on R's own internal C++ libraries:
# Create a vector with 500,000 items
n <- 500000
values <- paste0(sample(c("yes", "no"), n, replace = TRUE),
as.integer(runif(n, 0, 10000)))
# data looks like:
values[1:3]
#> [1] "no3697" "yes1906" "yes6738"
clean_logical(values[1:3])
#> [1] FALSE TRUE TRUE
clean_character(values[1:3])
#> [1] "no" "yes" "yes"
clean_numeric(values[1:3])
#> [1] 3697 1906 6738
# benchmark the cleaning based on 10 runs and show it in seconds:
microbenchmark::microbenchmark(logical = clean_logical(values),
character = clean_character(values),
numeric = clean_numeric(values),
times = 10,
unit = "s")
#> Unit: seconds
#> expr min lq mean median uq max neval
#> logical 0.2846163 0.2925479 0.3076008 0.3100244 0.3189712 0.3269428 10
#> character 0.4522698 0.4593437 0.4734631 0.4636837 0.4888959 0.5303473 10
#> numeric 0.6428362 0.6476207 0.6618845 0.6542312 0.6778215 0.6897005 10
Cleaning 500,000 values (!) only takes 0.3-0.6 seconds on our system.
Invalid regular expressions
If invalid regular expressions are used, the cleaning functions will not throw errors, but instead will show a warning and will interpret the expression as a fixed value:
clean_character("0123test 0123[a-b] ")
#> [1] "test ab"
clean_character("0123test 0123[a-b] ", remove = "[a-b]")
#> [1] "0123test 0123[-]"
clean_character("0123test0123", remove = "[a-b")
#> [1] "0123test 0123]"
#> Warning message:
#> invalid regular expression '[a-b', reason 'Missing ']'' - now interpreting as fixed value