Ensure Required Columns Are Present in a Data Frame

This utility function checks whether all expected columns are present in a given data frame. It is particularly useful for validating user input or internal data structures within a package, helping to prevent downstream errors caused by missing variables.

Usage

required_cols(df, expected, name)

Arguments

df

A data frame to be checked.

expected

A character vector of expected column names.

name

A character string indicating the name or source of the data frame (used in the error message).

Value

The function does not return anything. It throws an error if required columns are missing.

Examples

required_cols(data.frame(a = 1, b = 2), c("a", "b"), "example_df") # OK
#> Error in required_cols(data.frame(a = 1, b = 2), c("a", "b"), "example_df"): could not find function "required_cols"
if (FALSE) { # \dontrun{
required_cols(data.frame(a = 1), c("a", "b"), "example_df") # Error
} # }