davidgrupp
Error in membership function
In submited example I added for loop to iterate through all water temperatures:
var water = new LinguisticVariable("Water");
var cold = water.MembershipFunctions.AddTrapezoid("Cold", 0, 0, 20, 40);
var warm = water.MembershipFunctions.AddTriangle("Warm", 30, 50, 70);
var hot = water.MembershipFunctions.AddTrapezoid("Hot", 50, 80, 100, 100);
var power = new LinguisticVariable("Power");
var low = power.MembershipFunctions.AddTriangle("Low", 0, 25, 50);
var high = power.MembershipFunctions.AddTriangle("High", 25, 50, 75);
IFuzzyEngine fuzzyEngine = new FuzzyEngineFactory().Default();
var rule1 = Rule.If(water.Is(cold).Or(water.Is(warm))).Then(power.Is(high));
var rule2 = Rule.If(water.Is(hot)).Then(power.Is(low));
fuzzyEngine.Rules.Add(rule1, rule2);
// ------------------------ my edit ------------------------
for (int i = 0; i <= 100; i++)
{
var result = fuzzyEngine.Defuzzify(new { water = i });
Console.WriteLine($"water = {i} result= {result}");
}
// ------------------------ my edit ------------------------
Which give me:
water = 0 result = 50
water = 1 result = 50
water = 2 result = 50
water = 3 result = 50
water = 4 result = 50
water = 5 result = 50
water = 6 result = 50
water = 7 result = 50
water = 8 result = 50
water = 9 result = 50
water = 10 result = 50
water = 11 result = 50
water = 12 result = 50
water = 13 result = 50
water = 14 result = 50
water = 15 result = 50
water = 16 result = 50
water = 17 result = 50
water = 18 result = 50
water = 19 result = 50
water = 20 result = 50
water = 21 result = 50
water = 22 result = 50
water = 23 result = 50
water = 24 result = 50
water = 25 result = 50
water = 26 result = 50
water = 27 result = 50
water = 28 result = 50
water = 29 result = 50
water = 30 result = 50
water = 31 result = 50
water = 32 result = 50
water = 33 result = 50
water = 34 result = 50
water = 35 result = 50
water = 36 result = 50
water = 37 result = 50
water = 38 result = 50
water = 39 result = 50
water = 40 result = 50
water = 41 result = 50
water = 42 result = 50
water = 43 result = 50
water = 44 result = 50
water = 45 result = 50
water = 46 result = 50
water = 47 result = 50
water = 48 result = 50
water = 49 result = 50
water = 50 result = 50
water = 51 result = 49.193548387096776
water = 52 result = 48.4375
water = 53 result = 47.72727272727273
water = 54 result = 47.05882352941176
water = 55 result = 46.42857142857144
water = 56 result = 45.833333333333336
water = 57 result = 45.27027027027027
water = 58 result = 44.73684210526316
water = 59 result = 44.23076923076923
water = 60 result = 43.75000000000001
water = 61 result = 43.29268292682927
water = 62 result = 42.857142857142854
water = 63 result = 42.44186046511628
water = 64 result = 42.04545454545455
water = 65 result = 41.666666666666664
water = 66 result = 41.30434782608696
water = 67 result = 40.95744680851064
water = 68 result = 40.625
water = 69 result = 40.30612244897959
water = 70 result = 40
water = 71 result = 39.705882352941174
water = 72 result = 39.42307692307693
water = 73 result = 39.15094339622641
water = 74 result = 38.888888888888886
water = 75 result = 38.63636363636364
water = 76 result = 38.39285714285714
water = 77 result = 38.1578947368421
water = 78 result = 37.931034482758626
water = 79 result = 37.71186440677966
water = 80 result = 37.5
water = 81 result = 37.5
water = 82 result = 37.5
water = 83 result = 37.5
water = 84 result = 37.5
water = 85 result = 37.5
water = 86 result = 37.5
water = 87 result = 37.5
water = 88 result = 37.5
water = 89 result = 37.5
water = 90 result = 37.5
water = 91 result = 37.5
water = 92 result = 37.5
water = 93 result = 37.5
water = 94 result = 37.5
water = 95 result = 37.5
water = 96 result = 37.5
water = 97 result = 37.5
water = 98 result = 37.5
water = 99 result = 37.5
water = 100 result = 37.5
Why there are no result between 50 and 75? Also, there are no result between 25 and 50.
Same here, tried using this library in my uni assignment but kept getting wrong answers. Something is not right here
I believe you need to do fuzzyEngine = new FuzzyEngineFactory().Default(); for each iteration. It was pointed out in another issue the engine only works once. I haven't re-run your test with this to verify.
I have modified the code to create a new FuzzyEngine in each iteration, but the results still don't seem right. Using:
var water = new LinguisticVariable("Water");
var cold = water.MembershipFunctions.AddTrapezoid("Cold", 0, 0, 20, 40);
var warm = water.MembershipFunctions.AddTriangle("Warm", 30, 50, 70);
var hot = water.MembershipFunctions.AddTrapezoid("Hot", 50, 80, 100, 100);
var power = new LinguisticVariable("Power");
var low = power.MembershipFunctions.AddTriangle("Low", 0, 25, 50);
var high = power.MembershipFunctions.AddTriangle("High", 25, 50, 75);
FuzzyRule[] rules = new FuzzyRule[2];
rules[0] = Rule.If(water.Is(cold).Or(water.Is(warm))).Then(power.Is(high));
rules[1] = Rule.If(water.Is(hot)).Then(power.Is(low));
for (int i=0; i<=100; i+=10)
{
IFuzzyEngine fuzzyEngine = new FuzzyEngineFactory().Default();
fuzzyEngine.Rules.Add(rules[0], rules[1]);
Console.WriteLine("Temp: {0} Cold: {1} Warm: {2} Hot: {3} Result: {4}", i, cold.Fuzzify(i), warm.Fuzzify(i), hot.Fuzzify(i), fuzzyEngine.Defuzzify(new { water = i }));
}
Console.ReadLine();
gives the following results:
Temp: 0 Cold: 1 Warm: 0 Hot: 0 Result: 50 Temp: 10 Cold: 1 Warm: 0 Hot: 0 Result: 50 Temp: 20 Cold: 1 Warm: 0 Hot: 0 Result: 50 Temp: 30 Cold: 0.5 Warm: 0 Hot: 0 Result: 50 Temp: 40 Cold: 0 Warm: 0.5 Hot: 0 Result: 50 Temp: 50 Cold: 0 Warm: 1 Hot: 0 Result: 50 Temp: 60 Cold: 0 Warm: 0.5 Hot: 0.3333333333333333 Result: 43.75000000000001 Temp: 70 Cold: 0 Warm: 0 Hot: 0.6666666666666666 Result: 40 Temp: 80 Cold: 0 Warm: 0 Hot: 1 Result: 37.5 Temp: 90 Cold: 0 Warm: 0 Hot: 1 Result: 37.5 Temp: 100 Cold: 0 Warm: 0 Hot: 1 Result: 37.5
So, I understand the results at low temperatures - the membership of the "high" function is one, so it chooses the centre of the "high" triangle, which is 50. But at high water temperatures, I would expect the result to be the centre of the "low" triangle, which is 25. But instead we get 37.5 - so it seems to be computing the centre of both the high and low triangles, which is incorrect.
