powerjoin (version 0.1.0)

preprocess_inputs: Preprocess powerjoin inputs

Description

These functions are named after the tidyverse functions select, summarize, nest, pack, pivot_wider and pivot_longer and are designed to avoid repetition of key columns when preprocessing the data for a join. They should only be used in the x and y arguments of powerjoin join functions. No further transformation should be applied on top of them.

Usage

select_keys_and(.data, ...)
summarize_by_keys(.data, ...)
nest_by_keys(.data, ..., name = NULL)
pack_along_keys(.data, ..., name)
complete_keys(.data)

Value

A data frame identical to the .data but with a "powerjoin_preprocess"

attribute to be handled by the join functions

Arguments

.data

A data frame to pivot.

...

Additional arguments passed on to methods.

name

Name of created column

Details

Unlike their tidyverse counterparts these just add an attribute to the input and don't reshape it. The join function then preprocesses the inputs using these attributes and the keys.

Examples

# in practice you'll mostly use those in join function calls directly
x <- select_keys_and(head(iris, 2), Sepal.Width)
# all it does is add an attribute that will be processed by the join function
attr(x, "powerjoin_preprocess")
# see `?power_left_join` or README for practical examples