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nuggets (version 2.0.1)

remove_ill_conditions: Remove invalid conditions from a list

Description

From a given list of character vectors, remove those elements that are not valid conditions.

Usage

remove_ill_conditions(x, data)

Value

A list containing only those elements of x that are valid conditions.

Arguments

x

A list of character vectors, each representing a condition.

data

A matrix or data frame whose column names define valid predicates.

Author

Michal Burda

Details

A valid condition is a character vector of predicates, where each predicate corresponds to a column name in the supplied data frame or matrix. Empty character vectors and NULL elements are also considered valid conditions.

This function acts as a simple filter around is_condition(). It checks each element of x against the column names of data and removes those that contain invalid predicates. The result preserves only valid conditions and discards the invalid ones.

See Also

is_condition()

Examples

Run this code
d <- data.frame(foo = 1:5, bar = 1:5, blah = 1:5)

conds <- list(c("foo", "bar"), "blah", "invalid", character(0), NULL)
remove_ill_conditions(conds, d)
# keeps "foo","bar"; "blah"; empty; NULL

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