checkr
is a light-weight R package of expressive, assertive,
pipe-friendly functions to check the properties of common R objects.
In the case of failure the functions, which are designed to be used in scripts and packages, issue informative error messages.
For an overview of the functions see the checkr-naming
vignette and
for a comparison with similar packages see the assertive-programming
vignette.
The following code demonstrates the check_data()
function
library(checkr)
# the starwars data frame in the dplyr package fails many of these checks
check_data(dplyr::starwars, values = list(
height = c(66L, 264L),
name = "",
mass = c(20,1358, NA),
hair_color = c("blond", "brown", "black", NA),
gender = c("male", "female", "hermaphrodite", "none", NA)),
order = TRUE, nrow = c(81, 84), key = "hair_color", error = FALSE)
#> Error in cc_and(colnames): could not find function "cc_and"
checkr
uses objects to check the values of other objects using an
elegant and expressive syntax.
To check the class simply pass an object of the desired class.
y <- c(2,1,0,1,NA)
check_vector(y, values = numeric(0))
check_vector(y, values = integer(0))
#> Error: y must be class integer
To check that a vector does not include missing values pass a single non-missing value (of the correct class).
check_vector(y, 1)
#> Error: y must not include missing values
To allow it to include missing values include a missing value.
check_vector(y, c(1, NA))
And to check that it only includes missing values only pass a missing value (of the correct class)
check_vector(y, NA_real_)
#> Error: y must only include missing values
To check the range of a vector pass two non-missing values (as well as the missing value if required).
check_vector(y, c(0, 2, NA))
check_vector(y, c(-1, -10, NA))
#> Error in cc_and(values[1:2]): could not find function "cc_and"
To check the vector only includes specific values pass three or more
non-missing values or set only = TRUE
.
check_vector(y, c(0, 1, 2, NA))
check_vector(y, c(1, 1, 2, NA))
#> Error in cc_or(values): could not find function "cc_or"
check_vector(y, c(1, 2, NA), only = TRUE)
#> Error in cc_or(values): could not find function "cc_or"
By default, the name of an object is determined from the function call.
check_vector(list(x = 1))
#> Error: list(x = 1) must be an atomic vector
This simplifies things but results in less informative error messages when used in a pipe.
library(magrittr)
y %>% check_list()
#> Error: . must be a list
The argument x_name
can be used to override the name.
y %>% check_list(x_name = "y")
#> Error: y must be a list
The four wrapper functions check_lgl()
, check_int()
, check_dbl()
and check_str()
check whether an object is an attribute-less
non-missing scalar logical (flag), integer, double (number) or character
(string). They are really useful for checking the types of arguments in
functions
fun <- function(x) { check_lgl(x)}
fun(x = NA)
#> Error: x must not include missing values
fun(x = TRUE)
fun(x = 1)
#> Error: x must be class logical
Additional scalar wrappers are check_date()
and check_dttm()
for
scalar Date and POSIXct objects. Alternatively you can roll your own
using the more general check_scalar()
function.
To install the latest official release from CRAN
install.packages("checkr")
To install the latest development version from GitHub
install.packages("devtools")
devtools::install_github("poissonconsulting/err")
devtools::install_github("poissonconsulting/checkr")
To install the latest development version from the Poisson drat repository
install.packages("drat")
drat::addRepo("poissonconsulting")
install.packages("checkr")
To cite checkr in publications use:
Joe Thorley (2018). checkr: An R package for Assertive
Programming. Journal of Open Source Software, 3(23), 624. URL
https://doi.org/10.21105/joss.00624
A BibTeX entry for LaTeX users is
@Article{,
title = {checkr: {An} {R} package for {Assertive} {Programming}},
author = {Joe Thorley},
journal = {Journal of Open Source Software},
year = {2018},
volume = {3},
number = {23},
pages = {624},
url = {http://joss.theoj.org/papers/10.21105/joss.00624},
}
Please report any issues.
Pull requests are always welcome.
Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms.
Any scripts or data that you put into this service are public.
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