square_roi {neuroim2} | R Documentation |
Create a square region of interest
Description
This function creates a square region of interest (ROI) in a 3D volume, where the z-dimension is fixed at one voxel coordinate. The ROI is defined within a given NeuroVol or NeuroSpace instance.
Usage
square_roi(bvol, centroid, surround, fill = NULL, nonzero = FALSE, fixdim = 3)
Arguments
bvol |
A |
centroid |
A numeric vector of length 3, representing the center of the square ROI in voxel coordinates. |
surround |
A non-negative integer specifying the number of voxels on either side of the central voxel. |
fill |
An optional value or values to assign to the data slot of the resulting ROI. If not provided, no data will be assigned. |
nonzero |
A logical value indicating whether to keep only nonzero elements from |
fixdim |
A logical value indicating whether the fixed dimension is the third, or z, dimension. Default is TRUE. |
Value
An instance of class ROIVol
representing the square ROI.
Examples
sp1 <- NeuroSpace(c(10, 10, 10), c(1, 1, 1))
square <- square_roi(sp1, c(5, 5, 5), 1)
vox <- coords(square)
## a 3 X 3 X 1 grid
nrow(vox) == 9