Augment Function Fourier Discrete

Takes a numeric vector(s) or date and will return a tibble of one of the following:

• "sin"

• "cos"

• "sincos"

• c("sin","cos","sincos") When either of these values falls below zero, then zero else one

Usage

hai_fourier_discrete_augment(
  .data,
  .value,
  .period,
  .order,
  .names = "auto",
  .scale_type = c("sin", "cos", "sincos")
)

Arguments

.data

The data being passed that will be augmented by the function.

.value

This is passed rlang::enquo() to capture the vectors you want to augment.

.period

The number of observations that complete a cycle

.order

The fourier term order

.names

The default is "auto"

.scale_type

A character of one of the following: "sin","cos", or sincos" All can be passed by setting the param equal to c("sin","cos","sincos")

Value

A augmented tibble

Details

Takes a numeric vector or a date and will return a vector of one of the following:

• "sin"

• "cos"

• "sincos"

• c("sin","cos","sincos")

This function is intended to be used on its own in order to add columns to a tibble.

See also

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

Author

Steven P. Sanderson II, MPH

Examples

suppressPackageStartupMessages(library(dplyr))

len_out <- 24
by_unit <- "month"
start_date <- as.Date("2021-01-01")

data_tbl <- tibble(
  date_col = seq.Date(from = start_date, length.out = len_out, by = by_unit),
  a = rnorm(len_out),
  b = runif(len_out)
)

hai_fourier_discrete_augment(data_tbl, b, .period = 2 * 12, .order = 1, .scale_type = "sin")
#> # A tibble: 24 × 4
#>    date_col         a      b fourier_discrete_b_sin
#>    <date>       <dbl>  <dbl>                  <dbl>
#>  1 2021-01-01 -0.621  0.374                       1
#>  2 2021-02-01 -0.194  0.610                       1
#>  3 2021-03-01  0.394  0.514                       1
#>  4 2021-04-01 -0.0332 0.864                       1
#>  5 2021-05-01 -0.529  0.856                       1
#>  6 2021-06-01  3.07   0.738                       1
#>  7 2021-07-01 -1.42   0.0562                      1
#>  8 2021-08-01  0.331  0.799                       1
#>  9 2021-09-01 -1.76   0.0567                      1
#> 10 2021-10-01 -1.02   0.363                       1
#> # ℹ 14 more rows
hai_fourier_discrete_augment(data_tbl, b, .period = 2 * 12, .order = 1, .scale_type = "cos")
#> # A tibble: 24 × 4
#>    date_col         a      b fourier_discrete_b_cos
#>    <date>       <dbl>  <dbl>                  <dbl>
#>  1 2021-01-01 -0.621  0.374                       1
#>  2 2021-02-01 -0.194  0.610                       1
#>  3 2021-03-01  0.394  0.514                       1
#>  4 2021-04-01 -0.0332 0.864                       1
#>  5 2021-05-01 -0.529  0.856                       1
#>  6 2021-06-01  3.07   0.738                       1
#>  7 2021-07-01 -1.42   0.0562                      1
#>  8 2021-08-01  0.331  0.799                       1
#>  9 2021-09-01 -1.76   0.0567                      1
#> 10 2021-10-01 -1.02   0.363                       1
#> # ℹ 14 more rows