gen_hrf: Construct an HRF Instance

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

Construct an HRF Instance

Description

gen_hrf takes a raw function f(t) and returns an HRF (Hemodynamic Response Function) instance.

Usage

gen_hrf(
  hrf,
  lag = 0,
  width = 0,
  precision = 0.1,
  summate = TRUE,
  normalize = FALSE,
  name = "gen_hrf",
  span = NULL,
  ...
)

Arguments

hrf	A function mapping from time to signal.
lag	Optional lag in seconds.
width	Optional block width in seconds.
precision	Sampling precision in seconds.
summate	Whether to allow each impulse response function to "add" up (default: TRUE).
normalize	Rescale so that the peak of the output is 1 (default: FALSE).
name	The assigned name of the generated HRF.
span	The span of the HRF (maximum width in seconds after which function reverts to zero).
...	Extra parameters for the hrf function.

Value

An instance of type HRF inheriting from function.

Examples

## Generate an HRF using SPMG1 canonical HRF, a lag of 3, and a width of 2.
grf <- gen_hrf(hrf_spmg1, lag=3, width=2)
grf(0:20)

hg <- purrr::partial(hrf_gaussian, mean=4, sd=1)
grf <- gen_hrf(hg, lag=1, width=2)

vals <- grf(0:20)

bbuchsbaum/fmrireg documentation built on May 16, 2023, 10:56 a.m.