public FiniteStateMCLog RandomVisits(int numOfSteps)
{
var log = new FiniteStateMCLog(numOfSteps);
var inverseTemp = 1 / T;
var stateProbabilities = _stateEnergies.Select(e => Math.Exp(-(e * inverseTemp))).ToArray();
var p = StateEnergies.Divide(T).Negative().Exp();
p = p.Divide(p.Sum());
var cumulativeProbability = p.CumSum();
Stream trajectoriesStream = null;
if (OutputStream != null)
{
trajectoriesStream = OutputStream;
}
else if (OutputFileName != null)
{
trajectoriesStream = new FileStream(OutputFileName, FileMode.Create, FileAccess.Write, FileShare.Read);
}
Action <int> writeFunction;
BitWriter bs = null;
var numOfBits = (int)Math.Ceiling(Math.Log(StateEnergies.Length, 2.0));
switch (OutputStyle)
{
case 1:
writeFunction = (state => { trajectoriesStream.WriteByte((byte)(1 << state)); });
break;
case 2:
bs = new BitWriter(trajectoriesStream);
writeFunction = (state => { bs.WriteBits((ulong)state, numOfBits); });
break;
default:
writeFunction = (state => { trajectoriesStream.WriteByte((byte)state); });
break;
}
for (int stepIndex = 0; stepIndex < numOfSteps; stepIndex++)
{
var randomNum = _random.NextDouble();
CurrentState = cumulativeProbability.IndexOfFirstGreater(randomNum);
_stateVisits[CurrentState]++;
log.VisitLog[stepIndex] = CurrentState;
// Write trajectories
if (trajectoriesStream != null)
{
writeFunction(CurrentState);
}
}
// Dispose of the stream only if this funcion created it
if (trajectoriesStream != null && OutputStream == null)
{
trajectoriesStream.Dispose();
}
double sum = _stateVisits.Sum();
log.MeanOccupancy = _stateVisits.Select(v => v / sum).ToArray();
log.Entropy = -log.MeanOccupancy.Select(m => (m + 1e-16) * Math.Log(m + 1e-16)).Sum();
log.TheoreticalEntropy = -p.MultiplyElements(p.Ln()).Sum();
return(log);
}
public FiniteStateMCLog RunAndLog(int numOfSteps, int intervalBetweenLogEntries)
{
var numOfLogEntries = numOfSteps / intervalBetweenLogEntries;
var log = new FiniteStateMCLog(numOfLogEntries);
Stream trajectoriesStream = null;
if (OutputStream != null)
{
trajectoriesStream = OutputStream;
}
else if (OutputFileName != null)
{
trajectoriesStream = new FileStream(OutputFileName, FileMode.Create, FileAccess.Write, FileShare.Read);
}
Action <int> writeFunction;
BitWriter bs = null;
var numOfBits = (int)Math.Ceiling(Math.Log(StateEnergies.Length, 2.0));
switch (OutputStyle)
{
case 1:
writeFunction = (state => { trajectoriesStream.WriteByte((byte)(1 << state)); });
break;
case 2:
bs = new BitWriter(trajectoriesStream);
writeFunction = (state => { bs.WriteBits((ulong)state, numOfBits); });
break;
default:
writeFunction = (state => { trajectoriesStream.WriteByte((byte)state); });
break;
}
for (int stepIndex = 0; stepIndex < numOfSteps; stepIndex++)
{
var nextState = _random.Next(_stateEnergies.Length);
var shouldAccept = (_stateEnergies[CurrentState] > _stateEnergies[nextState]) ||
(_random.NextDouble() <
Math.Exp((_stateEnergies[CurrentState] - _stateEnergies[nextState]) / T));
if (shouldAccept)
{
CurrentState = nextState;
}
if (stepIndex % intervalBetweenLogEntries == 0)
{
_stateVisits[CurrentState]++;
log.VisitLog[stepIndex / intervalBetweenLogEntries] = CurrentState;
// Write trajectories
if (trajectoriesStream != null)
{
writeFunction(CurrentState);
}
}
}
// Dispose of the stream only if this funcion created it
if (trajectoriesStream != null && OutputStream == null)
{
trajectoriesStream.Dispose();
}
double sum = _stateVisits.Sum();
log.MeanOccupancy = _stateVisits.Select(v => v / sum).ToArray();
log.Entropy = -log.MeanOccupancy.Select(m => (m + 1e-16) * Math.Log(m + 1e-16)).Sum();
var p = StateEnergies.Divide(T).Negative().Exp();
p = p.Divide(p.Sum());
log.TheoreticalEntropy = -p.MultiplyElements(p.Ln()).Sum();
return(log);
}