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using System;
using Smile;
// Tutorial2 loads the XDSL file created by Tutorial1,
// then performs the series of inference calls,
// changing evidence each time.
namespace SmileNetTutorial
{
class Tutorial2
{
public static void Run()
{
Console.WriteLine("Starting Tutorial2...");
Network net = new Network();
// load the network created by Tutorial1
net.ReadFile("tutorial1.xdsl");
Console.WriteLine("Posteriors with no evidence set:");
net.UpdateBeliefs();
PrintAllPosteriors(net);
Console.WriteLine("Setting Forecast=Good.");
ChangeEvidenceAndUpdate(net, "Forecast", "Good");
Console.WriteLine("Adding Economy=Up.");
ChangeEvidenceAndUpdate(net, "Economy", "Up");
Console.WriteLine("Changing Forecast to Poor, keeping Economy=Up.");
ChangeEvidenceAndUpdate(net, "Forecast", "Poor");
Console.WriteLine(
"Removing evidence from Economy, keeping Forecast=Poor.");
ChangeEvidenceAndUpdate(net, "Economy", null);
Console.WriteLine("Tutorial2 complete.");
}
private static void PrintPosteriors(Network net, int nodeHandle)
{
String nodeId = net.GetNodeId(nodeHandle);
if (net.IsEvidence(nodeHandle))
{
Console.WriteLine("{0} has evidence set ({1})",
nodeId,
net.GetOutcomeId(nodeHandle, net.GetEvidence(nodeHandle)));
}
else
{
double[] posteriors = net.GetNodeValue(nodeHandle);
for (int i = 0; i < posteriors.Length; i++)
{
Console.WriteLine("P({0}={1})={2}",
nodeId,
net.GetOutcomeId(nodeHandle, i),
posteriors[i]);
}
}
}
private static void PrintAllPosteriors(Network net)
{
for (int h = net.GetFirstNode(); h >= 0; h = net.GetNextNode(h))
{
PrintPosteriors(net, h);
}
Console.WriteLine();
}
private static void ChangeEvidenceAndUpdate(
Network net, String nodeId, String outcomeId)
{
if (outcomeId != null)
{
net.SetEvidence(nodeId, outcomeId);
}
else
{
net.ClearEvidence(nodeId);
}
net.UpdateBeliefs();
PrintAllPosteriors(net);
}
}
}