calcGroupsMask: Compute spatial groups

Description

Compute the spatial groups defined by a binary parameter.

Usage

"calcGroupsMask"(object, mask, numeric2logical = FALSE, W = "ifany", W.range, W.spatial_res = c(1,1,1),
	 verbose = optionsMRIaggr("verbose"), update.object = FALSE, overwrite = TRUE)

Arguments

object

an object of class MRIaggr. REQUIRED.

mask

the binary contrast parameter that should be used to identifying the spatial groups. character. REQUIRED.

numeric2logical

should mask be convert to logical ? logical.

the neighbourhood matrix. dgCMatrix or "ifany" leading to use the neighbourhood matrix stored in the object if any and else computate this matrix.

W.range

the neighbourhood range. postive numeric. REQUIRED.

W.spatial_res

a dilatation factor for the coordinates. positive numeric vector of size 3.

verbose

should the execution of the function be traced ? logical.

update.object

should the resulting spatial groups be stored in object ? logical.

overwrite

if spatial groups are already stored in object@ls_descStats, can they be overwritten ? logical.

Value

An list containing for each parameter:

[[group]] : a vector containing the group index for each observation.
[[group_size]] : a vector with the size of each spatial group.
[[group_number]] : the number of spatial groups. integer vector.
[[group_max]] : the index of the largest group. integer vector.

Details

This function requires to have installed the Matrix and the spam package to work.

FUNCTION: Call the calcGroupsW function.

Examples

Run this code

## load a MRIaggr object
data("MRIaggr.Pat1_red", package = "MRIaggr")

## compute spatial groups
calcGroupsMask(MRIaggr.Pat1_red, mask = c("MASK_DWI_t0","MASK_T2_FLAIR_t2"),
               W.range = 6, W.spatial_res = c(1.875,1.875,6),
               update.object = TRUE, overwrite = TRUE)

## extract spatial groups
selectDescStats(MRIaggr.Pat1_red, "GroupsLesion")