volume.cluster.levels: Compute the iso-levels of the cluster shells.

In fsbrain: Managing and Visualizing Brain Surface Data

Compute the iso-levels of the cluster shells.

Description

Computes the iso-levels at which the shells of the clusters are extracted: num_levels levels from the threshold up to the highest level, for each requested sign, ordered from the outermost (the threshold) to the innermost (the highest level) shell.

Usage

volume.cluster.levels(
  volume,
  threshold,
  num_levels = 10L,
  max_level = NULL,
  max_level_quantile = 0.99,
  positive = TRUE,
  negative = TRUE
)

Arguments

volume	a 3D numerical array.
threshold	single positive number, the cluster threshold.
num_levels	positive integer, the number of levels per sign.
max_level	single positive number or NULL, the highest level. If NULL, it is computed per sign as the max_level_quantile quantile of the absolute values beyond the threshold.
max_level_quantile	single value between 0 and 1, the quantile used to compute max_level if that is NULL.
positive	logical, whether to compute levels for the positive side.
negative	logical, whether to compute levels for the negative side.

Value

numerical vector of iso-levels, the negative ones (if any) first, each ordered from the outermost to the innermost shell.

fsbrain documentation built on Sept. 27, 2026, 1:07 a.m.