simulate_spline: Add a spline-generated variable

In simulab: Simulates a Wide Variety of Data Shapes, Sizes and Distributions

Add a spline-generated variable

Description

Add a spline-generated variable

Usage

simulate_spline(
  data,
  predictor,
  variable,
  coefficients,
  knots = c(0.25, 0.5, 0.75),
  degree = 3L,
  output_range = NULL,
  noise_variance = 0,
  seed = NULL,
  batch = NULL
)

Arguments

data	Base data.frame.
predictor	Predictor variable.
variable	Name of the generated variable.
coefficients	Spline coefficients.
knots	Quantile probabilities for interior knots.
degree	Polynomial degree.
output_range	Optional numeric pair. The spline value v is rescaled to output_range[1] + v * diff(output_range), which maps ⁠[0, 1]⁠ onto the pair. Values outside ⁠[0, 1]⁠ are rescaled the same way, not clipped.
noise_variance	Non-negative Gaussian noise variance; the noise added to each value has standard deviation sqrt(noise_variance).
seed	Optional random seed.
batch	Optional single positive whole number. When given, the simulator runs batch times and returns a plain list of batch results, each exactly what the same call without batch returns. With a seed, every dataset gets its own seed drawn from seed, so the whole batch is reproducible; without one the datasets are consecutive draws from the session's random-number stream. The default NULL returns a single result.

Value

A simulab_sim base data.frame holding data with the spline variable added. as.data.frame(x, what = "basis") gives the tidy basis table, one row per observation/basis combination, and as.data.frame(x, what = "parameters") gives one row per basis coefficient.

Examples

data <- data.frame(id = 1:100, x = stats::runif(100))
result <- simulate_spline(
  data, predictor = "x", variable = "y",
  coefficients = c(0.1, 0.2, 0.5, 0.4, 0.7, 0.6, 0.9),
  knots = c(0.25, 0.5, 0.75), seed = 1
)
head(result)

simulab documentation built on Oct. 15, 2026, 5:08 p.m.