Bridging Python and SMILE C++ Libraries For Linux Smile library availiable at: http://genie.sis.pitt.edu/index.php/downloads version used: Linux (x64) / gcc 4.4.5, March 6th 2013

Makefile

CXX= g++
CXXFILES= pysmilebridge.cpp
CXXINTERMEDIATE= pysmilebridge.o
CXXOUTPUTLIBS= libpysmilebridge.so
CXXFLAGS= -O3 -DNDEBUG -ffast-math -Wall -fPIC
LIBS = -L/path/to/smile/ -lsmile

all: lib

lib:
        $(CXX) $(CXXFLAGS) $(LIBS) -c $(CXXFILES)
        $(CXX) -shared -o $(CXXOUTPUTLIBS) $(CXXINTERMEDIATE) $(LIBS)

pybridgetest.py

import ctypes

pysmilebridge = ctypes.CDLL("/path/to/pysmilebridge/libpysmilebridge.so")
pysmilebridge.CreateNetwork()

pysmilebridge.cpp

#include <iostream>
#include <sstream>
#include <iomanip>
using namespace std;

#include "smile/smile.h"

extern "C" {
  
  void CreateNetwork(void) {
    DSL_network theNet;
    
    // create node "Success"
    int success = theNet.AddNode(DSL_CPT,"Success");
    
    // setting number (and name) of outcomes
    DSL_idArray someNames;
    someNames.Add("Success");
    someNames.Add("Failure");
    theNet.GetNode(success)->Definition()->SetNumberOfOutcomes(someNames);  
 
    // create node "Forecast"
    int forecast = theNet.AddNode(DSL_CPT,"Forecast");
 
    // setting number (and name) of outcomes
    someNames.Flush();
    someNames.Add("Good");
    someNames.Add("Moderate");
    someNames.Add("Poor");
    theNet.GetNode(forecast)->Definition()->SetNumberOfOutcomes(someNames);  
    
     // add arc from "Success" to "Forecast"
     theNet.AddArc(success,forecast);
    
    // now fill in the conditional distribution for node "Success" using
    // direct method. The probabilities are:
    // P("Success" = Success) = 0.2
    // P("Success" = Failure) = 0.8 
    DSL_doubleArray theProbs;
    theProbs.SetSize(2); // it has to be an array
    theProbs[0] = 0.2;
    theProbs[1] = 0.8;
    theNet.GetNode(success)->Definition()->SetDefinition(theProbs);
 
    // now fill in the conditional distribution for node "Forecast" using a system of 
    // coordinates. The probabilities are:
    // P("Forecast" = Good | "Success" = Success) = 0.4
    // P("Forecast" = Moderate | "Success" = Success) = 0.4
    // P("Forecast" = Poor | "Success" = Success) = 0.2
    // P("Forecast" = Good | "Success" = Failure) = 0.1
    // P("Forecast" = Moderate | "Success" = Failure) = 0.3
    // P("Forecast" = Poor | "Success" = Failure) = 0.6
    DSL_sysCoordinates theCoordinates (*theNet.GetNode(forecast)->Definition());
    theCoordinates.UncheckedValue() = 0.4;
    theCoordinates.Next();
    theCoordinates.UncheckedValue() = 0.4;
    theCoordinates.Next();
    theCoordinates.UncheckedValue() = 0.2;
    theCoordinates.Next();
    theCoordinates.UncheckedValue() = 0.1;
    theCoordinates.Next();
    theCoordinates.UncheckedValue() = 0.3;
    theCoordinates.Next();
    theCoordinates.UncheckedValue() = 0.6; 
    theNet.WriteFile("tutorial.dsl");
  };

}