grapes-twiddle-grapes: Distributional assignment operator

In RTMB: 'R' Bindings for 'TMB'

Distributional assignment operator

Description

Distributional assignment operator

Usage

x %~% distr

Arguments

x	LHS; Random effect or data for which distribution assignment applies
distr	RHS; Distribution expression

Details

Provides a slightly simplified syntax inspired by, but not compatible with, other probabilistic programming languages (e.g. BUGS/JAGS):

• x %~% distribution(...) is syntactic sugar for .nll <- .nll - sum(distribution(x,...,log=TRUE))

• The variable .nll is automatically initialized to 0 and returned on exit.

Value

The updated value of the hidden variable .nll.

Note

If the shorter name ~ is preferred, it can be locally overloaded using "~" <- RTMB::"%~%".

Examples

f <- function(parms) {
  getAll(parms)
  x %~% dnorm(mu, 1)
  y %~% dpois(exp(x))
}
p <- list(mu=0, x=numeric(10))
y <- 1:10
obj <- MakeADFun(f, p, random="x")

RTMB documentation built on Sept. 12, 2024, 6:45 a.m.