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using System;
using Smile;
// Tutorial8 loads continuous model from the XDSL file written by Tutorial7,
// then adds discrete nodes to create a hybrid model. Inference is performed
// and model is saved to disk.
namespace SmileNetTutorial
{
class Tutorial8
{
public static void Run()
{
Console.WriteLine("Starting Tutorial8...");
Network net = new Network();
net.ReadFile("tutorial7.xdsl");
CreateCptNode(
net, "zone", "Climate Zone",
new String[] { "Temperate", "Desert" },
60, 20);
int toaHandle = net.GetNode("toa");
net.SetNodeEquation(toaHandle,
"toa=If(zone=\"Desert\",Normal(22,5),Normal(11,10))");
int perceivedHandle = CreateCptNode(
net, "perceived", "Perceived Temperature",
new String[] { "Hot", "Warm", "Cold" },
60, 300);
net.AddArc(toaHandle, perceivedHandle);
double[] perceivedProbs = new double[] {
0, // P(perceived=Hot |toa in -10..0)
0.02, // P(perceived=Warm|toa in -10..0)
0.98, // P(perceived=Cold|toa in -10..0)
0.05, // P(perceived=Hot |toa in 0..10)
0.15, // P(perceived=Warm|toa in 0..10)
0.80, // P(perceived=Cold|toa in 0..10)
0.10, // P(perceived=Hot |toa in 10..20)
0.80, // P(perceived=Warm|toa in 10..20)
0.10, // P(perceived=Cold|toa in 10..20)
0.80, // P(perceived=Hot |toa in 20..30)
0.15, // P(perceived=Warm|toa in 20..30)
0.05, // P(perceived=Cold|toa in 20..30)
0.98, // P(perceived=Hot |toa in 30..40)
0.02, // P(perceived=Warm|toa in 30..40)
0 // P(perceived=Cold|toa in 30..40)
};
net.SetNodeDefinition(perceivedHandle, perceivedProbs);
net.SetEvidence("zone", "Temperate");
Console.WriteLine("Results in temperate zone:");
UpdateAndShowStats(net);
net.SetEvidence("zone", "Desert");
Console.WriteLine("Results in desert zone:\n");
UpdateAndShowStats(net);
net.WriteFile("tutorial8.xdsl");
Console.WriteLine("Tutorial8 complete: Network written to tutorial8.xdsl");
}
private static int CreateEquationNode(
Network net, String id, String name,
String equation, double loBound, double hiBound,
int xPos, int yPos)
{
int handle = net.AddNode(Network.NodeType.Equation, id);
net.SetNodeName(handle, name);
net.SetNodePosition(handle, xPos, yPos, 85, 55);
net.SetNodeEquation(handle, equation);
net.SetNodeEquationBounds(handle, loBound, hiBound);
return handle;
}
private static void ShowStats(Network net, int nodeHandle)
{
String nodeId = net.GetNodeId(nodeHandle);
if (net.IsEvidence(nodeHandle))
{
double v = net.GetContEvidence(nodeHandle);
Console.WriteLine("{0} has evidence set ({1})", nodeId, v);
return;
}
if (net.IsValueDiscretized(nodeHandle))
{
Console.WriteLine("{0} is discretized.", nodeId);
DiscretizationInterval[] iv =
net.GetNodeEquationDiscretization(nodeHandle);
double[] bounds = net.GetNodeEquationBounds(nodeHandle);
double[] discBeliefs = net.GetNodeValue(nodeHandle);
double lo = bounds[0];
for (int i = 0; i < discBeliefs.Length; i++)
{
double hi = iv[i].Boundary;
Console.WriteLine("\tP({0} in {1}..{2})={3}",
nodeId, lo, hi, discBeliefs[i]);
lo = hi;
}
}
else
{
double[] stats = net.GetNodeSampleStats(nodeHandle);
Console.WriteLine("{0}: mean={1} stddev={2} min={3} max={4}",
nodeId, stats[0], stats[1], stats[2], stats[3]);
}
}
private static void UpdateAndShowStats(Network net)
{
net.UpdateBeliefs();
for (int h = net.GetFirstNode(); h >= 0; h = net.GetNextNode(h))
{
if (net.GetNodeType(h) == (int)Network.NodeType.Equation)
{
ShowStats(net, h);
}
}
Console.WriteLine();
}
private static int CreateCptNode(
Network net, String id, String name,
String[] outcomes, int xPos, int yPos)
{
int handle = net.AddNode(Network.NodeType.Cpt, id);
net.SetNodeName(handle, name);
net.SetNodePosition(handle, xPos, yPos, 85, 55);
int initialOutcomeCount = net.GetOutcomeCount(handle);
for (int i = 0; i < initialOutcomeCount; i++)
{
net.SetOutcomeId(handle, i, outcomes[i]);
}
for (int i = initialOutcomeCount; i < outcomes.Length; i++)
{
net.AddOutcome(handle, outcomes[i]);
}
return handle;
}
}
}