Derive the upper bound of an "intermediate" gate

WHAT: among the marker-positive cells, find the valley separating the intermediate mode from the bright mode; that valley is the upper bound. WHY: "CD14 int CD16 int" is a genuine three-level gate (negative / intermediate / bright), and monocyte subsetting depends on it. Returns NA when the positive fraction has no second valley – the population is then reported UNAVAILABLE rather than being silently merged with the bright subset.

Usage

derive_intermediate_bounds(tmat, thr, parent, spec)

Arguments

tmat

The tmat.

thr

The thr.

parent

The parent.

spec

Population specification mapping population name to marker directions. See default_population_spec().