LogicalNeuroVol Class

This class represents a three-dimensional brain image where all values are either TRUE or FALSE. It is particularly useful for creating and managing binary masks for brain images.

This function constructs a LogicalNeuroVol instance.

Usage

LogicalNeuroVol(data, space, label = "", indices = NULL)

Arguments

data: A three-dimensional array, a 1D vector with length equal to prod(dim(space)), or a set of indices where elements are TRUE.
space: An instance of class NeuroSpace.
label: A character string.
indices: An optional 1-d index vector.

Value

A LogicalNeuroVol instance.

Details

The LogicalNeuroVol class extends the DenseNeuroVol class, inheriting its spatial properties and array-based storage. However, it constrains the values to be logical (TRUE or FALSE), making it ideal for representing binary masks, regions of interest (ROIs), or segmentation results in neuroimaging analyses.

Slots

.Data: A logical array containing the binary volume data.
space: A NeuroSpace object defining the spatial properties of the volume.

Methods

This class inherits methods from DenseNeuroVol. Additional methods specific to logical operations may be available.

Examples

# Create a simple logical brain volume (e.g., a mask)
dim <- c(64L, 64L, 64L)
mask_data <- array(sample(c(TRUE, FALSE), prod(dim), replace = TRUE), dim)
mask_space <- NeuroSpace(dim = dim, origin = c(0, 0, 0), spacing = c(1, 1, 1))
brain_mask <- new("LogicalNeuroVol", .Data = mask_data, space = mask_space)

# Check the proportion of TRUE voxels
true_proportion <- sum(brain_mask) / prod(dim(brain_mask))
print(paste("Proportion of TRUE voxels:", true_proportion))
#> [1] "Proportion of TRUE voxels: 0.500446319580078"

# Load an example brain mask
brain_mask <- read_vol(system.file("extdata", "global_mask_v4.nii", package="neuroim2"))

# Convert the brain mask to a LogicalNeuroVol
logical_vol <- LogicalNeuroVol(brain_mask, space(brain_mask))