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// tutorial6.cpp
// Tutorial6 creates a dynamic Bayesian network (DBN),
// performs the inference, then saves the model to disk.
#include "smile.h"
#include <cstdio>
static int CreateCptNode(
DSL_network& net, const char* id, const char* name,
std::initializer_list<const char*> outcomes, int xPos, int yPos);
static void UpdateAndShowTemporalResults(DSL_network &net);
int Tutorial6()
{
printf("Starting Tutorial6...\n");
DSL_errorH().RedirectToFile(stdout);
DSL_network net;
int loc = CreateCptNode(net, "Location", "Location",
{ "Pittsburgh", "Sahara" }, 160, 360);
int rain = CreateCptNode(net, "Rain", "Rain",
{ "true", "false" }, 380, 240);
int umb = CreateCptNode(net, "Umbrella", "Umbrella",
{ "true", "false" }, 300, 100);
net.SetTemporalType(rain, dsl_temporalType::dsl_plateNode);
net.SetTemporalType(umb, dsl_temporalType::dsl_plateNode);
net.AddArc(loc, rain);
net.AddTemporalArc(rain, rain, 1);
net.AddArc(rain, umb);
DSL_nodeDef *rainDef = net.GetNode(rain)->Def();
int res = rainDef->SetDefinition({
0.7, // P(Rain=true |Location=Pittsburgh)
0.3, // P(Rain=false|Location=Pittsburgh)
0.01, // P(Rain=true |Location=Sahara)
0.99 // P(Rain=false|Location=Sahara)
});
if (DSL_OKAY != res)
{
return res;
}
res = rainDef->SetTemporalDefinition(1, {
0.7, // P(Rain=true |Location=Pittsburgh,Rain[t-1]=true)
0.3, // P(Rain=false|Location=Pittsburgh,Rain[t-1]=true)
0.3, // P(Rain=true |Location=Pittsburgh,Rain[t-1]=false)
0.7, // P(Rain=false|Location=Pittsburgh,Rain[t-1]=false)
0.001, // P(Rain=true |Location=Sahara,Rain[t-1]=true)
0.999, // P(Rain=false|Location=Sahara,Rain[t-1]=true)
0.01, // P(Rain=true |Location=Sahara,Rain[t-1]=false)
0.99 // P(Rain=false|Location=Sahara,Rain[t-1]=false)
});
if (DSL_OKAY != res)
{
return res;
}
res = net.GetNode(umb)->Def()->SetDefinition({
0.9, // P(Umbrella=true |Rain=true)
0.1, // P(Umbrella=false|Rain=true)
0.2, // P(Umbrella=true |Rain=false)
0.8 // P(Umbrella=false|Rain=false)
});
if (DSL_OKAY != res)
{
return res;
}
net.SetNumberOfSlices(5);
printf("Performing update without evidence.\n");
UpdateAndShowTemporalResults(net);
printf("Setting Umbrella[t=1] to true and Umbrella[t=3] to false.\n");
res = net.GetNode(umb)->Val()->SetTemporalEvidence(1, 0);
if (DSL_OKAY != res)
{
return res;
}
res = net.GetNode(umb)->Val()->SetTemporalEvidence(3, 1);
if (DSL_OKAY != res)
{
return res;
}
UpdateAndShowTemporalResults(net);
res = net.WriteFile("tutorial6.xdsl");
if (DSL_OKAY != res)
{
return res;
}
printf("Tutorial6 complete: Network written to tutorial6.xdsl\n");
return DSL_OKAY;
}
static void UpdateAndShowTemporalResults(DSL_network &net)
{
net.UpdateBeliefs();
int sliceCount = net.GetNumberOfSlices();
for (int h = net.GetFirstNode(); h >= 0; h = net.GetNextNode(h))
{
if (net.GetTemporalType(h) == dsl_temporalType::dsl_plateNode)
{
DSL_node *node = net.GetNode(h);
int outcomeCount = node->Def()->GetNumberOfOutcomes();
printf("Temporal beliefs for %s:\n", node->GetId());
const DSL_Dmatrix& mtx = *node->Val()->GetMatrix();
for (int sliceIdx = 0; sliceIdx < sliceCount; sliceIdx++)
{
printf("\tt=%d:", sliceIdx);
for (int i = 0; i < outcomeCount; i++)
{
printf(" %f", mtx[sliceIdx * outcomeCount + i]);
}
printf("\n");
}
}
}
printf("\n");
}
static int CreateCptNode(
DSL_network& net, const char* id, const char* name,
std::initializer_list<const char*> outcomes, int xPos, int yPos)
{
int handle = net.AddNode(DSL_CPT, id);
DSL_node* node = net.GetNode(handle);
node->SetName(name);
node->Def()->SetNumberOfOutcomes(outcomes);
DSL_rectangle& position = node->Info().Screen().position;
position.center_X = xPos;
position.center_Y = yPos;
position.width = 85;
position.height = 55;
return handle;
}