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library(rSMILE)
source("License.R")
printPosteriors = function(net, nodeHandle) {
nodeId <- net$getNodeId(nodeHandle)
if(net$isEvidence(nodeHandle)) {
cat(sprintf("%s has evidence set (%s)\n",
nodeId,
net$getOutcomeId(nodeHandle, net$getEvidence(nodeHandle))))
} else {
posteriors <- net$getNodeValue(nodeHandle)
for (i in 0:(length(posteriors)-1)) {
cat(sprintf("P(%s=%s)=%f\n",
nodeId, net$getOutcomeId(nodeHandle, i),posteriors[i+1]))
}
}
}
printAllPosteriors = function(net) {
nodes <- net$getAllNodes()
for (h in nodes) {
printPosteriors(net, h)
}
cat("\n")
}
changeEvidenceAndUpdate = function(net, nodeId, outcomeId) {
if (is.null(outcomeId)) {
net$clearEvidence(nodeId)
} else {
net$setEvidence(nodeId, outcomeId)
}
net$updateBeliefs()
printAllPosteriors(net)
}
cat("Starting Tutorial2...\n")
net <- Network()
# load the network created by Tutorial1
net$readFile("tutorial1.xdsl")
cat("Posteriors with no evidence set:\n")
net$updateBeliefs()
printAllPosteriors(net)
cat("Setting Forecast=Good.\n");
changeEvidenceAndUpdate(net, "Forecast", "Good");
cat("Adding Economy=Up.\n");
changeEvidenceAndUpdate(net, "Economy", "Up");
cat("Changing Forecast to Poor, keeping Economy=Up.\n");
changeEvidenceAndUpdate(net, "Forecast", "Poor");
cat("Removing evidence from Economy, keeping Forecast=Poor.\n");
changeEvidenceAndUpdate(net, "Economy", NULL);
cat("Tutorial2 complete.\n");