# R/getDelta.R In lcc: Longitudinal Concordance Correlation

#### Documented in getDelta

```#######################################################################
#                                                                     #
# Package: lcc                                                        #
#                                                                     #
# File: getDelta.R                                                    #
# Contains: getDelta function                                         #
#                                                                     #
# Written by Thiago de Paula Oliveira                                 #
# copyright (c) 2017-18, Thiago P. Oliveira                           #
#                                                                     #
# First version: 11/10/2017                                           #
# Last update: 29/07/2019                                             #
# License: GNU General Public License version 2 (June, 1991) or later #
#                                                                     #
#######################################################################
##' @title Internal Function to Extract Variance Components Estimates.
##'
##' @usage NULL
##'
##' @description This is an internally called function used to extract
##'   variance components estimate of \eqn{\Sigma} matrix based on
##'   specified structure.
##'
##' @author Thiago de Paula Oliveira,
##'   \email{thiago.paula.oliveira@@alumni.usp.br} and Rafael de Andrade Moral,
##'   \email{rafael_moral@@yahoo.com.br}
##'
##' @keywords internal
getDelta <- function(model) {
varcomp <- summary(model)
if(is.null(varcomp\$modelStruct\$varStruct)) {
delta <- deltal <- 0
g1 <- function(x) 1
g<-g1
} else {
var.f <- class(varcomp\$modelStruct\$varStruct)[1]
if(var.f == "varIdent") {
components2 <-
c(1, exp(as.numeric(varcomp\$modelStruct\$varStruct))^2)
delta <- 1
deltal <- components2[-1]
g2 <- function(x) x
g<-g2
}
if(var.f == "varExp") {
if(attr(varcomp\$modelStruct\$varStruct, "formula")==~time){
delta=deltal <- varcomp\$modelStruct\$varStruct
g <- function(x, tk) exp(2*x*tk)
} else{if(attr(varcomp\$modelStruct\$varStruct, "formula")==~time | method){
components2 <- as.numeric(varcomp\$modelStruct\$varStruct)
delta=components2[1]
deltal <- components2[-1]
g3 <- function(x, tk) exp(2*x*tk)
g<-g3
}
}
}
}
return(list(delta=delta, deltal=deltal, g=g))
}
```

## Try the lcc package in your browser

Any scripts or data that you put into this service are public.

lcc documentation built on Feb. 26, 2021, 5:07 p.m.