/// <summary>
/// Predict the next item most likey from the given one.
/// We assume arrays of sequence items has NValue -1 elements in it
/// </summary>
/// <param name="sequence">a sequence of NValue-1 items</param>
/// <returns></returns>
public string PredictNext(string[] sequence)
{
if (sequence.Length != NValue - 1)
{
throw new Exception("Bad set of sequence items. The member count is not the same as the NValue-1!");
}
string key = GetStringName(sequence);
if (!data.ContainsKey(key))
{
PredictedProbabilty = 0;
return("Unknown");
}
KeyDataRecord keyData = data[key];
//find the highest probability
int highestValue = 0;
string bestItem = "Unknown";
//Get the list of items in the store
ICollection <string> possibleItems = keyData.counts.Keys;
//Go through each
foreach (string ds in possibleItems)
{
//Check for the highest value
if (keyData.counts[ds] > highestValue)
{
//Store the item
highestValue = keyData.counts[ds];
bestItem = ds;
}
}
//calculate probability
if (total > 0)
{
PredictedProbabilty = ((double)highestValue / (double)keyData.total) * 100.0;
}
return(bestItem);
}
/// <summary>
/// Register a set of input sequnces with predictor,
/// updating its data. We assume the sequence has exactly NValue in it
/// </summary>
/// <param name="sequence">a sequence of NValue item</param>
public void RegisterSequence(string[] sequences)
{
if (sequences.Length != NValue)
{
throw new Exception("Bad set of sequences. The member count is not the same as the N value!");
}
total++;
string[] previousSeq = new string[NValue - 1];
for (int i = 0; i < NValue - 1; i++)
{
previousSeq[i] = sequences[i];
}
string currentSeq = sequences[NValue - 1];
string key = GetStringName(previousSeq);
if (!data.ContainsKey(key))
{
data[key] = new KeyDataRecord();
}
KeyDataRecord keyData = data[key];
if (keyData.counts == null)
{
keyData.counts = new Dictionary <string, int>();
}
if (!keyData.counts.ContainsKey(currentSeq))
{
keyData.counts[currentSeq] = 0;
}
keyData.counts[currentSeq] = keyData.counts[currentSeq] + 1;
keyData.total += 1;
data[key] = keyData;
}
