Construct an HRF Instance using Decorators

`gen_hrf` takes a base HRF function or object and applies optional lag, blocking, and normalization decorators based on arguments.

Usage

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

Arguments

hrf: A function `f(t)` or an existing `HRF` object.
lag: Optional lag in seconds. If non-zero, applies `lag_hrf`.
width: Optional block width in seconds. If non-zero, applies `block_hrf`.
precision: Sampling precision for block convolution (passed to `block_hrf`). Default is 0.1.
half_life: Half-life decay parameter for exponential decay in seconds (passed to `block_hrf`). Default is Inf (no decay).
summate: Whether to summate within blocks (passed to `block_hrf`). Default is TRUE.
normalize: If TRUE, applies `normalise_hrf` at the end. Default is FALSE.
name: Optional name for the *final* HRF object. If NULL (default), a name is generated based on the base HRF and applied decorators.
span: Optional span for the *final* HRF object. If NULL (default), the span is determined by the base HRF and decorators.
...: Extra arguments passed to the *base* HRF function if `hrf` is a function.

Value

A final `HRF` object, potentially modified by decorators.

Examples

# Lagged SPMG1
grf_lag <- gen_hrf(HRF_SPMG1, lag=3)
# Blocked Gaussian
grf_block <- gen_hrf(hrf_gaussian, width=5, precision=0.2)
# Lagged and Blocked, then Normalized
grf_both_norm <- gen_hrf(HRF_SPMG1, lag=2, width=4, normalize=TRUE)