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MRIaggr (version 1.1.5)

initGR: Growing Region initialization

Description

Initialize arguments of the Growing Region algorithm. For internal use.

Usage

initGR(contrast, W, seed, sigma_max, range, range.seed, breaks, iter_max, sd.robust, keep.lower, keep.upper, history.sigma, history.step, history.front, rescale, verbose, method = "initGR")

Arguments

contrast
the contrast value of each observation. numeric vector.
W
the neighbourhood matrix. dgCMatrix.
seed
the index of the initial seeds or a binary indicator of the initial seeds. positive integer vector or logical vector.
sigma_max
the maximum admissible value for the variability of the group contrast. positive numeric.
range
the range of acceptable contrast values for the growing region group. numeric vector of size 2.
range.seed
the range of acceptable contrast values for the seeds. numeric vector of size 2.
breaks
the break points or the number of break points to use to categorize the contrast distribution. numeric vector or postive integer.
iter_max
the maximum number of iterations for the expansion of the growing region. postive integer.
sd.robust
should the median absolute deviation be used to estimte the variability of the group contrast, or the standard deviation ? logical.
keep.lower
should removing observations with high intensity of the region be forbidden ? logical.
keep.upper
should removing observations with low intensity of the region be forbidden ? logical.
history.sigma
should the values of sigma be recorded ? logical.
history.step
should the number of observations included in the growing region set be recorded ? logical.
history.front
should the propagation front of the GR set be recorded ? logical.
rescale
should the contrast be scaled ? logical.
verbose
should the execution of the function be traced ? logical.
method
the name of the function that called the initializer. character.