Project a rectangular frame to the legacy GDS cube — as_gds.fmri

This compatibility projection is deliberately strict. The selected observation annotations must define one complete, unique Cartesian product of subject and contrast keys. Ragged frames remain frames and are rejected rather than padded with implicit slabs.

Usage

# S3 method for class 'fmri_frame'
as_gds(
  x,
  subject = "subject_id",
  contrast = "contrast_id",
  subjects = NULL,
  contrasts = NULL,
  assay_names = names(fmridataset::assays(x)),
  assay_map = NULL,
  memory_budget = 2 * 1024^3,
  metadata = list(),
  ...
)

Arguments

x: An fmri_frame or synchronized frame view.
subject, contrast: Observation columns defining the rectangular axes. Either may be NULL only for an explicit singleton axis.
subjects, contrasts: Optional explicit axis order or singleton label. A NULL subject column defaults to a singleton "meta" axis; a NULL contrast column defaults to "contrast1".
assay_names: Assays to realize into the cube.
assay_map: Named character vector mapping frame assay names to GDS assay names. By default variance becomes var and std_error becomes se.
memory_budget: Maximum total bytes realized across projected assays.
metadata: Additional GDS metadata.
...: Reserved for future use.

Value

A realized legacy gds compatibility projection.