/// <summary>
/// Computes the grade for attempt using all the possible metrics
/// </summary>
/// <param name="dfaGoal">minimal correct dfa</param>
/// <param name="dfaAttempt">dfa to be graded</param>
/// <param name="al">input alphabet</param>
/// <param name="solver">SMT solver for char set</param>
/// <param name="timeout">timeout for the PDL enumeration (suggested > 1000)</param>
/// <param name="maxGrade">Max grade for the homework</param>
/// <param name="enableDFAED">true to enable DFA edit distance</param>
/// <param name="enablePDLED">true to enable PDL edit distance</param>
/// <param name="enableDensity">true to enable density distance</param>
/// <returns>Grade for dfa2</returns>
public static Pair <int, IEnumerable <DFAFeedback> > GetGrade(
Automaton <BDD> dfaGoal, Automaton <BDD> dfaAttempt, HashSet <char> al,
CharSetSolver solver, long timeout,
int maxGrade, FeedbackLevel level,
bool enableDFAED, bool enablePDLED, bool enableDensity)
{
PDLEnumerator pdlEnumerator = new PDLEnumerator();
var feedList = new List <DFAFeedback>();
DFAFeedback defaultFeedback = new StringFeedback(level, StringFeedbackType.Wrong, al, solver);
#region Accessory and initial vars
//Compute minimized version of DFAs
var dfaGoalMin = dfaGoal.Determinize(solver).Minimize(solver);
var dfaAttemptMin = dfaAttempt.Determinize(solver).Minimize(solver);
//Initialize distances at high values in case they are not used
// they only produce positive grade if between 0 and 1
double pdlEditDistanceScaled = 2;
double densityRatio = 2;
double dfaED = 2;
#endregion
#region deductions on the grade based on the size of the dfa
//Deduction if DFA is smaller than it should be: used only for PDL ed and for density
var smallerDFADeduction = 0.2 * Math.Sqrt(
Math.Max(0.0, dfaGoalMin.StateCount - dfaAttemptMin.StateCount) /
((double)dfaGoalMin.StateCount));
#endregion
#region check whether the attempt is equivalent to the solution
if (dfaGoal.IsEquivalentWith(dfaAttempt, solver))
{
Console.WriteLine("Correct");
feedList.Add(new StringFeedback(level, StringFeedbackType.Correct, al, solver));
return(new Pair <int, IEnumerable <DFAFeedback> >(maxGrade, feedList));
}
#endregion
#region metrics computation
Stopwatch swPDLed = new Stopwatch();
swPDLed.Start();
#region PDL edit distance
Transformation feedbackTransformation = null;
if (enablePDLED)
{
var trpair = PDLEditDistance.GetMinimalFormulaEditDistanceTransformation(dfaGoalMin, dfaAttemptMin, al, solver, timeout, pdlEnumerator);
if (trpair != null)
{
var transformationGrade = trpair.First;
feedbackTransformation = trpair.Second;
var scaling = 1.0;
pdlEditDistanceScaled = transformationGrade.totalCost / (transformationGrade.minSizeForTreeA * scaling) + smallerDFADeduction;
}
}
#endregion
swPDLed.Stop();
Stopwatch swDensity = new Stopwatch();
swDensity.Start();
#region density distance
if (enableDensity)
{
densityRatio = DFADensity.GetDFADifferenceRatio(dfaGoalMin, dfaAttemptMin, al, solver);
densityRatio += smallerDFADeduction;
}
#endregion
swDensity.Stop();
Stopwatch swDFAed = new Stopwatch();
swDFAed.Start();
#region DFA edit distance
DFAEditScript dfaEditScript = null;
if (enableDFAED)
{
//limit the depth of the DFA edit distance search
var maxMoves = Math.Max(1, 6 - (int)Math.Sqrt(dfaAttempt.MoveCount + dfaAttempt.StateCount));
dfaEditScript = DFAEditDistance.GetDFAOptimalEdit(dfaGoal, dfaAttempt, al, solver, timeout, new StringBuilder());
if (dfaEditScript != null)
{
dfaED = ((double)(dfaEditScript.GetCost())) / ((double)((dfaGoalMin.StateCount + 1) * al.Count));
}
}
#endregion
swDFAed.Stop();
#endregion
#region metrics scaling
var scalingSquarePDLED = 1.005;
var scalingSquareDensity = 1; var multv2 = 0.5;
var scalingSquareDFAED = 1.03;
var scaledPdlED = (0.9 * (scalingSquarePDLED + pdlEditDistanceScaled) * (scalingSquarePDLED + pdlEditDistanceScaled)) - scalingSquarePDLED * scalingSquarePDLED;
var scaledDensityRatio = (scalingSquareDensity + (multv2 * densityRatio)) * (scalingSquareDensity + (multv2 * densityRatio)) - scalingSquareDensity * scalingSquareDensity;
var scaledDfaED = (scalingSquareDFAED + dfaED) * (scalingSquareDFAED + dfaED) - scalingSquareDFAED * scalingSquareDFAED;
//Select dominating Feedback based on grade
double unscaledGrade = Math.Min(Math.Min(scaledPdlED, scaledDensityRatio), scaledDfaED);
var pdledwins = scaledPdlED <= Math.Min(scaledDensityRatio, scaledDfaED);
var dfaedwins = scaledDfaED <= Math.Min(scaledDensityRatio, scaledPdlED);
var densitywins = scaledDensityRatio <= Math.Min(scaledDfaED, scaledPdlED);
#endregion
#region Feedback Selection
if (pdledwins && feedbackTransformation != null && feedbackTransformation.pdlB.GetFormulaSize() < 10)
{
feedList.Add(new PDLEDFeedback(level, al, feedbackTransformation, scaledPdlED, solver));
}
if ((dfaedwins || feedList.Count == 0) && dfaEditScript != null && !dfaEditScript.IsComplex())
{
feedList = new List <DFAFeedback>();
feedList.Add(new DFAEDFeedback(dfaGoal, dfaAttempt, level, al, dfaEditScript, scaledDfaED, solver));
}
if (densitywins || feedList.Count == 0)
{
feedList = new List <DFAFeedback>();
feedList.Add(new DensityFeedback(level, al, dfaGoal, dfaAttempt, scaledDensityRatio, solver));
}
if (feedList.Count == 0)
{
Console.WriteLine("Why no feedback!!");
feedList.Add(defaultFeedback);
}
#endregion
#region normalize grade
var scaledGrade = maxGrade - (int)Math.Round(unscaledGrade * (double)(maxGrade));
//If rounding yields maxgrade deduct 1 point by default
if (scaledGrade == maxGrade)
{
scaledGrade = maxGrade - 1;
}
//Remove possible deduction
scaledGrade = scaledGrade < 0 ? 0 : scaledGrade;
return(new Pair <int, IEnumerable <DFAFeedback> >(scaledGrade, feedList));
#endregion
}
/// <summary>
/// Computes the grade for attempt using all the possible metrics
/// </summary>
/// <param name="dfaGoal">minimal correct dfa</param>
/// <param name="dfaAttempt">dfa to be graded</param>
/// <param name="al">input alphabet</param>
/// <param name="solver">SMT solver for char set</param>
/// <param name="timeout">timeout for the PDL enumeration (suggested > 1000)</param>
/// <param name="maxGrade">Max grade for the homework</param>
/// <param name="enableDFAED">true to enable DFA edit distance</param>
/// <param name="enablePDLED">true to enable PDL edit distance</param>
/// <param name="enableDensity">true to enable density distance</param>
/// <returns>Grade for dfa2</returns>
public static Pair<int, IEnumerable<DFAFeedback>> GetGrade(
Automaton<BDD> dfaGoal, Automaton<BDD> dfaAttempt, HashSet<char> al,
CharSetSolver solver, long timeout,
int maxGrade, FeedbackLevel level,
bool enableDFAED, bool enablePDLED, bool enableDensity)
{
PDLEnumerator pdlEnumerator = new PDLEnumerator();
var feedList = new List<DFAFeedback>();
DFAFeedback defaultFeedback = new StringFeedback(level, StringFeedbackType.Wrong, al, solver);
#region Accessory and initial vars
//Compute minimized version of DFAs
var dfaGoalMin = dfaGoal.Determinize(solver).Minimize(solver);
var dfaAttemptMin = dfaAttempt.Determinize(solver).Minimize(solver);
//Initialize distances at high values in case they are not used
// they only produce positive grade if between 0 and 1
double pdlEditDistanceScaled = 2;
double densityRatio = 2;
double dfaED = 2;
#endregion
#region deductions on the grade based on the size of the dfa
//Deduction if DFA is smaller than it should be: used only for PDL ed and for density
var smallerDFADeduction = 0.2 * Math.Sqrt(
Math.Max(0.0, dfaGoalMin.StateCount - dfaAttemptMin.StateCount) /
((double)dfaGoalMin.StateCount));
#endregion
#region check whether the attempt is equivalent to the solution
if (dfaGoal.IsEquivalentWith(dfaAttempt, solver))
{
Console.WriteLine("Correct");
feedList.Add(new StringFeedback(level, StringFeedbackType.Correct, al, solver));
return new Pair<int, IEnumerable<DFAFeedback>>(maxGrade, feedList);
}
#endregion
#region metrics computation
Stopwatch swPDLed = new Stopwatch();
swPDLed.Start();
#region PDL edit distance
Transformation feedbackTransformation = null;
if (enablePDLED)
{
var trpair = PDLEditDistance.GetMinimalFormulaEditDistanceTransformation(dfaGoalMin, dfaAttemptMin, al, solver, timeout, pdlEnumerator);
if (trpair != null)
{
var transformationGrade = trpair.First;
feedbackTransformation = trpair.Second;
var scaling = 1.0;
pdlEditDistanceScaled = transformationGrade.totalCost / (transformationGrade.minSizeForTreeA * scaling) + smallerDFADeduction;
}
}
#endregion
swPDLed.Stop();
Stopwatch swDensity = new Stopwatch();
swDensity.Start();
#region density distance
if (enableDensity)
{
densityRatio = DFADensity.GetDFADifferenceRatio(dfaGoalMin, dfaAttemptMin, al, solver);
densityRatio += smallerDFADeduction;
}
#endregion
swDensity.Stop();
Stopwatch swDFAed = new Stopwatch();
swDFAed.Start();
#region DFA edit distance
DFAEditScript dfaEditScript = null;
if (enableDFAED)
{
//limit the depth of the DFA edit distance search
var maxMoves = Math.Max(1, 6 - (int)Math.Sqrt(dfaAttempt.MoveCount + dfaAttempt.StateCount));
dfaEditScript = DFAEditDistance.GetDFAOptimalEdit(dfaGoal, dfaAttempt, al, solver, timeout, new StringBuilder());
if (dfaEditScript != null)
dfaED = ((double)(dfaEditScript.GetCost())) / ((double)((dfaGoalMin.StateCount + 1) * al.Count));
}
#endregion
swDFAed.Stop();
#endregion
#region metrics scaling
var scalingSquarePDLED = 1.005;
var scalingSquareDensity = 1; var multv2 = 0.5;
var scalingSquareDFAED = 1.03;
var scaledPdlED = (0.9 * (scalingSquarePDLED + pdlEditDistanceScaled) * (scalingSquarePDLED + pdlEditDistanceScaled)) - scalingSquarePDLED * scalingSquarePDLED;
var scaledDensityRatio = (scalingSquareDensity + (multv2 * densityRatio)) * (scalingSquareDensity + (multv2 * densityRatio)) - scalingSquareDensity * scalingSquareDensity;
var scaledDfaED = (scalingSquareDFAED + dfaED) * (scalingSquareDFAED + dfaED) - scalingSquareDFAED * scalingSquareDFAED;
//Select dominating Feedback based on grade
double unscaledGrade = Math.Min(Math.Min(scaledPdlED, scaledDensityRatio), scaledDfaED);
var pdledwins = scaledPdlED <= Math.Min(scaledDensityRatio, scaledDfaED);
var dfaedwins = scaledDfaED <= Math.Min(scaledDensityRatio, scaledPdlED);
var densitywins = scaledDensityRatio <= Math.Min(scaledDfaED, scaledPdlED);
#endregion
#region Feedback Selection
if (pdledwins && feedbackTransformation != null && feedbackTransformation.pdlB.GetFormulaSize()<10)
feedList.Add(new PDLEDFeedback(level, al, feedbackTransformation, scaledPdlED, solver));
if ((dfaedwins || feedList.Count == 0) && dfaEditScript != null && !dfaEditScript.IsComplex())
{
feedList = new List<DFAFeedback>();
feedList.Add(new DFAEDFeedback(dfaGoal, dfaAttempt, level, al, dfaEditScript, scaledDfaED, solver));
}
if (densitywins || feedList.Count == 0)
{
feedList = new List<DFAFeedback>();
feedList.Add(new DensityFeedback(level, al, dfaGoal, dfaAttempt, scaledDensityRatio, solver));
}
if (feedList.Count == 0)
{
Console.WriteLine("Why no feedback!!");
feedList.Add(defaultFeedback);
}
#endregion
#region normalize grade
var scaledGrade = maxGrade - (int)Math.Round(unscaledGrade * (double)(maxGrade));
//If rounding yields maxgrade deduct 1 point by default
if (scaledGrade == maxGrade)
scaledGrade = maxGrade - 1;
//Remove possible deduction
scaledGrade = scaledGrade < 0 ? 0 : scaledGrade;
return new Pair<int, IEnumerable<DFAFeedback>>(scaledGrade, feedList);
#endregion
}