validate (version 1.0.2)

occurs: Count how often a value of value combination occurs

Description

For each row in a data frame, count how many similar rows there are. The ... argument is used to specify which variables are taken into account. Missing values are counted as a unique value.

Usage

occurs(...)

Arguments

...

When used in a validation rule: a bare (unquoted) list of variable names. When used directly, a comma-separated list of vectors of equal length.

Value

For each record it indicates how often the value or value combination in the arguments occur.

Examples

# NOT RUN {
# for each element i the sequence (a,b,c,a,c,a) 
# compute how often it occurrs in the sequence.
occurs(c("a","b","c","a","c","a")) 

# for each record in 'iris' how often do the same
# (Sepal.Length, Species) combinations occur?
with(iris, occurs(Sepal.Length, Species))

# in the context of a validation. Check whether
# each individual Species occurs at least 10 times.

rules <- validator(occurs(Species) > 10)
cf <- confront(iris, rules)
summary(cf)

# }