rule {dataverifyr}

Creates a single data rule

Description

Creates a single data rule

Usage

rule(expr, name = NA, allow_na = FALSE, negate = FALSE, ...)

## S3 method for class 'rule'
print(x, ...)

Arguments

expr

an expression which dictates which determines when a rule is good. Note that the expression is evaluated in check_data(), within the given framework. That means, for example if a the data given to check_data() is an arrow dataset, the expression must be mappable from arrow (see also arrow documentation). The expression can be given as a string as well.

name

an optional name for the rule for reference

allow_na

does the rule allow for NA values in the data? default value is FALSE. Note that when NAs are introduced in the expression, allow_na has no effect. Eg when the rule as.numeric(vs) %in% c(0, 1) finds the values of vs as c("1", "A"), the rule will throw a fail regardless of the value of allow_na as the NA is introduced in the expression and is not found in the original data. However, when the values of vs are c("1", NA), allow_na will have an effect.

negate

is the rule negated, only applies to the expression not allow_na, that is, if expr = mpg > 10, allow_na = TRUE, and negate = TRUE, it would match all mpg <= 10 as well as NAs.

...

additional arguments that are carried along for your documentation, but are not used. Could be for example date, person, contact, comment, etc

x

a rule to print

Value

The rule values as a list

Methods (by generic)

• print(rule): Prints a rule

Examples

r <- rule(mpg > 10)
r

r2 <- rule(mpg > 10, name = "check that mpg is reasonable", allow_na = TRUE,
           negate = FALSE, author = "me", date = Sys.Date())
r2

check_data(mtcars, r)

rs <- ruleset(
  rule(mpg > 10),
  rule(cyl %in% c(4, 6)), # missing 8
  rule(qsec >= 14.5 & qsec <= 22.9)
)
rs
check_data(mtcars, rs)