/// <summary>
/// Returns the probability for the given random variables. If it is not present yet, it is calculated first.
/// All access to _probs should be through this method!
/// </summary>
/// <param name="variables">random variables for the distribution</param>
/// <returns></returns>
private Probability GetProbability(ICollection <RandomVariable> variables)
{
var index = SubsetUtils.GetIndex(variables, _randomVariables);
if (!_probs.ContainsKey(index))
{
_probs[index] = CalculateProbability(variables.ToList());
if (!string.IsNullOrWhiteSpace(_config.ProbabilitySerializationFilePath))
{
SerializeCurrentProbabilities();
}
}
return(_probs[index]);
}
private void DeserializeProbabilities()
{
using (var file = File.OpenText(_config.ProbabilityDeserializationFilePath))
{
var serializer = new JsonSerializer();
var probs = (ProbabilitySerialization)serializer.Deserialize(file, typeof(ProbabilitySerialization));
foreach (var keyValuePair in probs.Probs)
{
var storedIndex = keyValuePair.Key;
var storedRandomVariables = SubsetUtils.FromIndex(probs.RandomVariables, storedIndex);
var realRandomVariables = _randomVariables.Where(rvar => storedRandomVariables.Contains(rvar.Name)).ToList();
_probs[SubsetUtils.GetIndex(realRandomVariables, _randomVariables)] = keyValuePair.Value;
if (realRandomVariables.Count == 1)
{
realRandomVariables[0].Probability = new[] { keyValuePair.Value, keyValuePair.Value.Complement() };
}
}
}
}
/// <summary>
/// Calculates all probability distributions of all subsets of the random variables.
/// Use with caution!
/// </summary>
public void CalculateTrueProbabilities()
{
// Iterate through all 2^n random variables
for (var i = 1; i < (1 << _randomVariables.Count); i++)
{
var currentVars = new HashSet <RandomVariable>();
for (var j = 0; j < _randomVariables.Count; j++)
{
// is the jth random variable present in the current subset?
// it is, if there is a 1 at the jth bit from the right side
// so 'and' i and 2^j and test if the result is greater than zero
if ((i & (1 << j)) > 0)
{
currentVars.Add(_randomVariables[j]);
}
}
_probs[SubsetUtils.GetIndex(currentVars, _randomVariables)] = CalculateProbability(currentVars.ToList());
}
WriteProbsToConsole();
}
