mask_vals-methods: Extract or Replace Values Inside a Mask

In neurobase: 'Neuroconductor' Base Package with Helper Functions for 'nifti' Objects

Extract or Replace Values Inside a Mask

Description

Methods that act on the .Data field in a NIfTI/ANALYZE image but only on values inside a mask.

Usage

mask_vals(object, mask)

mask_vals(object, mask) <- value

## S4 replacement method for signature 'nifti'
mask_vals(object, mask) <- value

## S4 replacement method for signature 'anlz'
mask_vals(object, mask) <- value

## S4 replacement method for signature 'array'
mask_vals(object, mask) <- value

Arguments

object	is an object of class nifti or anlz.
mask	is an object of class nifti or anlz.
value	is the value to assign to the .Data field.

Examples

set.seed(2022)
img = nifti(array(rnorm(10^3), dim = rep(10, 3)))
mask = img > 1.5
mask_vals(img, mask)
testthat::expect_equal(sum(mask_vals(img, mask)), 117.628200302518)
mask_vals(img, mask) = rep(4, sum(mask))
mask_vals(img, as(mask, "array")) = rep(4, sum(mask))
mask_vals(as(img, "array"), 
    as(mask, "array")) = rep(4, sum(mask))

neurobase documentation built on Oct. 23, 2022, 5:05 p.m.