fmx (version 0.1.2)

fmx_constraint: Parameter Constraint(s) of Mixture Distribution

Description

Determine the parameter constraint(s) of a finite mixture distribution fmx, either by the value of parameters of such mixture distribution, or by a user-specified string.

Usage

fmx_constraint(
  dist,
  distname = dist@distname,
  K = dim(dist@pars)[1L],
  pars = dist@pars
)

Value

Function fmx_constraint returns the indices of internal parameters (only applicable to Tukey \(g\)-&-\(h\) mixture distribution, yet) to be constrained, based on the input fmx object dist.

Arguments

dist

(optional) fmx object

distname

character scalar, name of distribution (see fmx), default value determined by dist

K

integer scalar, number of components, default value determined by dist

pars

double matrix, distribution parameters of a finite mixture distribution (see fmx), default value determined by dist

Examples

(d0 = fmx('GH', A = c(1,4), g = c(.2,.1), h = c(.05,.1), w = c(1,1)))
(c0 = fmx_constraint(d0))
user_constraint(character(), distname = 'GH', K = 2L) # equivalent

(d1 = fmx('GH', A = c(1,4), g = c(.2,0), h = c(0,.1), w = c(1,1)))
(c1 = fmx_constraint(d1))
user_constraint(c('g2', 'h1'), distname = 'GH', K = 2L) # equivalent

(d2 = fmx('GH', A = c(1,4), g = c(.2,0), h = c(.15,.1), w = c(1,1)))
(c2 = fmx_constraint(d2))
user_constraint('g2', distname = 'GH', K = 2L) # equivalent