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jags.R    147 lines (132 with data), 4.9 kB

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print.jags <- function(x, ...)
{
model <- x$model()
for (i in 1:length(model)) {
cat(model[i],"\n",sep="")
}
}
jags.model <- function(file, data, inits, nchain = 1)
{
if (missing(file)) {
stop("Model file name missing")
}
p <- .Call("make_console", PACKAGE="rjags")
.Call("check_model", p, file, PACKAGE="rjags")
if (is.environment(data)) {
##Get a list of numeric objects from the supplied environment
varnames <- .Call("get_variable_names", p, PACKAGE="rjags")
data <- mget(varnames, envir=data, mode="numeric", ifnotfound=list(NULL))
}
.Call("compile", p, data, as.integer(nchain), TRUE, PACKAGE="rjags")
setParameters <- function(initsi, chain) {
if (!is.list(initsi))
stop("Parameters must be a list")
if (is.null(names(initsi)) || any(nchar(names(initsi)) == 0))
stop("Parameters must be a named list")
if (!is.null(initsi[[".RNG.name"]])) {
.Call("set_rng_name", p, initsi[[".RNG.name"]], PACKAGE="rjags")
inits[[".RNG.name"]] <- NULL
}
.Call("set_parameters", p, initsi, as.integer(chain), PACKAGE="rjags")
}
if (!missing(inits)) {
if (!is.list(inits)) {
stop("Initial values must be a list")
}
if (length(inits) != nchain) {
stop("inits list must be the same length as the number of chains")
}
for (i in 1:nchain) {
setParameters(inits[[i]], i)
}
}
.Call("initialize", p, PACKAGE="rjags")
model.state <- .Call("get_state", p, PACKAGE="rjags")
model.data <- .Call("get_data", p, PACKAGE="rjags")
model.code <- readLines(file)
model <- list("ptr" = function() {p},
"data" = function() {model.data},
"model" = function() {model.code},
"state" = function(internal=FALSE)
{
if(!internal) {
for(i in 1:nchain) {
model.state[[i]][[".RNG.state"]] <- NULL
model.state[[i]][[".RNG.name"]] <- NULL
model.state[[i]][[".Iteration"]] <- NULL
}
}
return(model.state)
},
"update" = function(niter, by) {
.Call("update", p, niter, PACKAGE="rjags")
model.state <<- .Call("get_state", p, PACKAGE="rjags")
invisible(NULL)
},
"recompile" = function() {
## Clear the console
.Call("clear_console", p, PACKAGE="rjags")
p <<- .Call("make_console", PACKAGE="rjags")
## Write the model to a temporary file so we can re-read it
mf <- tempfile()
writeLines(model.code, mf)
.Call("check_model", p, mf, PACKAGE="rjags")
unlink(mf)
## Re-compile
.Call("compile", p, data, nchain, FALSE, PACKAGE="rjags")
## Re-initialize
if (!is.null(model.state)) {
if (length(model.state) != nchain) {
stop("Incorrect number of chains in saved state")
}
for (i in 1:nchain) {
statei <- model.state[[i]]
rng <- statei[[".RNG.name"]]
if (!is.null(rng)) {
.Call("set_rng_name", p, rng, i, PACKAGE="rjags")
statei[[".RNG.name"]] <- NULL
}
.Call("set_parameters", p, statei, i, PACKAGE="rjags")
}
.Call("initialize", p, PACKAGE="rjags")
}
invisible(NULL)
})
class(model) <- "jags"
return(model)
}
read.jagsdata <- function(file)
{
e <- new.env()
eval(parse(file), e)
return(as.list(e))
}
model.samples <- function(model, variable.names, n.iter, thin=1)
{
if (class(model) != "jags")
stop("Invalid JAGS model")
if (!is.character(variable.names))
stop("variable.names must be a character vector")
if (length(variable.names) == 0)
stop("Empty variable name list")
if (!is.numeric(n.iter) || length(n.iter) != 1 || n.iter <= 0)
stop("n.iter must be a positive integer")
for (i in seq(along=variable.names)) {
.Call("set_monitor", model$ptr(), variable.names[i], thin, PACKAGE="rjags")
}
model$update(as.integer(n.iter))
nchain <- length(model$state())
if (nchain == 1) {
ans <- .Call("get_monitored_values", model$ptr(), 1, PACKAGE="rjags")
}
else {
ans <- vector("list", nchain)
for (i in 1:length(ans)) {
ans[[i]] <- .Call("get_monitored_values", model$ptr(), i, PACKAGE="rjags")
}
}
for (i in seq(along=variable.names)) {
.Call("clear_monitor", model$ptr(), variable.names[i], PACKAGE="rjags")
}
return(ans)
}