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package tutorials;
import smile.*;
// Tutorial7 creates a network with three equation-based nodes
// performs the inference, then saves the model to disk.
public class Tutorial7 {
public static void run() {
System.out.println("Starting Tutorial7...");
Network net = new Network();
net.setOutlierRejectionEnabled(true);
createEquationNode(net,
"tra", "Return Air Temperature",
"tra=24", 23.9, 24.1,
280, 100);
createEquationNode(net,
"u_d", "Damper Control Signal",
"u_d = Bernoulli(0.539)*0.8 + 0.2", 0, 1,
160, 100);
int toa = createEquationNode(net,
"toa", "Outside Air Temperature",
"toa=Normal(11,15)", -10, 40,
60, 100);
// tra, toa and u_d are referenced in equation
// arcs are created automatically
int tma = createEquationNode(net,
"tma", "Mixed Air Temperature",
"tma=toa*u_d+(tra-tra*u_d)", 10, 30,
110, 200);
setUniformIntervals(net, toa, 5);
setUniformIntervals(net, tma, 4);
System.out.println("Results with no evidence:");
updateAndShowStats(net);
net.setContEvidence(toa, 28.5);
System.out.println("Results with outside air temperature set to 28.5:");
updateAndShowStats(net);
net.clearEvidence(toa);
System.out.println("Results with mixed air temperature set to 21:");
net.setContEvidence(tma, 21.0);
updateAndShowStats(net);
net.writeFile("tutorial7.xdsl");
System.out.println("Tutorial7 complete: Network written to tutorial7.xdsl");
}
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.setNodeEquation(handle, equation);
net.setNodeEquationBounds(handle, loBound, hiBound);
net.setNodePosition(handle, xPos, yPos, 85, 55);
return handle;
}
static void showStats(Network net, int nodeHandle) {
String nodeId = net.getNodeId(nodeHandle);
if (net.isEvidence(nodeHandle)) {
double v = net.getContEvidence(nodeHandle);
System.out.printf("%s has evidence set (%g)\n", nodeId, v);
return;
}
if (net.isValueDiscretized(nodeHandle)) {
System.out.printf("%s is discretized.\n", 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;
System.out.printf(
"\tP(%s in %g..%g)=%g\n", nodeId, lo, hi, discBeliefs[i]);
lo = hi;
}
} else {
double[] stats = net.getNodeSampleStats(nodeHandle);
System.out.printf("%s: mean=%g stddev=%g min=%g max=%g\n",
nodeId, stats[0], stats[1], stats[2], stats[3]);
}
}
static void setUniformIntervals(Network net, int nodeHandle, int count) {
double[] bounds = net.getNodeEquationBounds(nodeHandle);
double lo = bounds[0];
double hi = bounds[1];
DiscretizationInterval[] iv = new DiscretizationInterval[count];
for (int i = 0; i < count; i++) {
iv[i] = new DiscretizationInterval(
null, lo + (i + 1) * (hi - lo) / count);
}
net.setNodeEquationDiscretization(nodeHandle, iv);
}
static void updateAndShowStats(Network net) {
net.updateBeliefs();
for (int h = net.getFirstNode(); h >= 0; h = net.getNextNode(h))
{
showStats(net, h);
}
System.out.println();
}
}