Convert an event_term to a per-condition basis list — condition_basis

A lightweight wrapper around convolve() that post-processes the resulting design matrix into a named list of T x d matrices - one per experimental condition ("base condition tag"). This keeps all of the heavy lifting inside fmrireg while exposing a minimal, pipe-friendly API that can be used anywhere a condition -> basis split is required (e.g. for CFALS).

Usage

condition_basis_list(
  x,
  hrf,
  sampling_frame,
  ...,
  output = c("condition_list", "matrix")
)

Arguments

x: An event_term object.
hrf: An HRF object to apply.
sampling_frame: A sampling_frame object defining the temporal grid.
...: Further arguments passed on to convolve() (e.g. drop.empty = FALSE).
output: Either "matrix" (default) for the ordinary design matrix or "condition_list" for the split-by-condition list.

Value

A numeric matrix or a named list of matrices, depending on output.

Examples

term <- event_term(
  list(condition = factor(c("A", "B", "A"))),
  onsets = c(0, 10, 20),
  blockids = c(1, 1, 1)
)
sf <- fmrihrf::sampling_frame(blocklens = 30, TR = 1)
condition_basis_list(term, fmrihrf::HRF_SPMG1, sf)
#> $condition.A
#> # A tibble: 30 × 1
#>    condition.A
#>          <dbl>
#>  1    0.000242
#>  2    0.0150  
#>  3    0.0671  
#>  4    0.132   
#>  5    0.170   
#>  6    0.171   
#>  7    0.145   
#>  8    0.108   
#>  9    0.0731  
#> 10    0.0439  
#> # ℹ 20 more rows
#> 
#> $condition.B
#> # A tibble: 30 × 1
#>    condition.B
#>          <dbl>
#>  1           0
#>  2           0
#>  3           0
#>  4           0
#>  5           0
#>  6           0
#>  7           0
#>  8           0
#>  9           0
#> 10           0
#> # ℹ 20 more rows
#>