create_event_model: Create an event model directly from components.

In bbuchsbaum/fmrireg: R package for the anlysis of fmri data

Create an event model directly from components.

Description

Constructs an event model from its components. Variables can be specified as character strings or expressions (captured using rlang::exprs). The function creates HRF specifications (hrfspec objects), builds a formula string, and then assembles the final event model.

Usage

create_event_model(
  event_terms,
  events,
  onsets,
  block,
  sampling_frame,
  durations = 0,
  drop_empty = TRUE,
  precision = 0.3
)

Arguments

event_terms	A list of event term specifications. Each term is a list with components: - variables: Character vector of variable names or expressions. - hrf: HRF specification for the term.
events	A data frame of event variables (all variables must be present).
onsets	A numeric vector of event onset times (in seconds).
block	A vector of block IDs (must be strictly increasing integers).
sampling_frame	The time series grid over which to sample the function.
durations	A numeric vector of event durations (default is 0 for all events).
drop_empty	Logical indicating whether to drop empty events (default is TRUE).
precision	Numeric value indicating the precision of HRF sampling (default is 0.3).

Value

An event_model object.

Examples

# Example with variables as character strings:
event_terms <- list(
  list(
    variables = c("x", "y"),
    hrf = "spmg1"
  )
)

# Example with variables as expressions:
event_terms <- list(
  list(
    variables = exprs(x, Poly(y, 2)),
    hrf = "spmg1"
  )
)

bbuchsbaum/fmrireg documentation built on March 1, 2025, 11:20 a.m.