hai_polynomial_augment: Augment Polynomial Features

In healthyR.ai: The Machine Learning and AI Modeling Companion to 'healthyR'

Augment Polynomial Features

Description

This function takes in a data table and a predictor column. A user can either create their own formula using the .formula parameter or, if they leave the default of NULL then the user must enter a .degree AND .pred_col column.

Usage

hai_polynomial_augment(
  .data,
  .formula = NULL,
  .pred_col = NULL,
  .degree = 1,
  .new_col_prefix = "nt_"
)

Arguments

.data	The data being passed that will be augmented by the function.
.formula	This should be a valid formula like 'y ~ .^2' or NULL.
.pred_col	This is passed rlang::enquo() to capture the vector that you designate as the 'y' column.
.degree	This should be an integer and is used to set the degree in the poly function. The degree must be less than the unique data points or it will error out.
.new_col_prefix	The default is "nt_" which stands for "new_term". You can set this to whatever you like, as long as it is a quoted string.

Details

A valid data.frame/tibble must be passed to this function. It is required that a user either enter a .formula or a .degree AND .pred_col otherwise this function will stop and error out.

Under the hood this function will create a stats::poly() function if the .formula is left as NULL. For example:

• .formula = A ~ .^2

• OR .degree = 2, .pred_col = A

There is also a parameter .new_col_prefix which will add a character string to the column names so that they are easily identified further down the line. The default is 'nt_'

Value

An augmented tibble

Author(s)

Steven P. Sanderson II, MPH

See Also

Other Augment Function: hai_fourier_augment(), hai_fourier_discrete_augment(), hai_hyperbolic_augment(), hai_scale_zero_one_augment(), hai_scale_zscore_augment(), hai_winsorized_move_augment(), hai_winsorized_truncate_augment()

Examples

suppressPackageStartupMessages(library(dplyr))
data_tbl <- data.frame(
  A = c(0, 2, 4),
  B = c(1, 3, 5),
  C = c(2, 4, 6)
)

hai_polynomial_augment(.data = data_tbl, .pred_col = A, .degree = 2, .new_col_prefix = "n")
hai_polynomial_augment(.data = data_tbl, .formula = A ~ .^2, .degree = 1)

healthyR.ai documentation built on April 3, 2023, 5:24 p.m.