public void TestAccepts03()
{
var productions = new HashSet <Production> {
CFGParser.Production("<S> -> <S> <S> <S>"),
CFGParser.Production("<S> -> ε"),
CFGParser.Production("<S> -> 'x2' 'x0'"),
CFGParser.Production("<S> -> 'x0' <S>"),
CFGParser.Production("<S> -> 'x4'"),
CFGParser.Production("<S> -> <S> 'x0' 'x4'"),
CFGParser.Production("<S> -> 'x3' <S> 'x3' <S> 'x0'"),
CFGParser.Production("<S> -> 'x2' <S> <S> <S> <S>"),
CFGParser.Production("<S> -> <S> <S> <S> <S> <S>"),
CFGParser.Production("<S> -> 'x0' <S> <S>"),
CFGParser.Production("<S> -> <S>"),
CFGParser.Production("<S> -> 'x0' <S> <S> 'x1'"),
CFGParser.Production("<S> -> 'x3' 'x2' 'x1'"),
CFGParser.Production("<S> -> 'x0' 'x0' 'x2'"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("S"));
CNFGrammar h = g.ToCNF();
Assert.IsTrue(h.Accepts(Sentence.FromLetters("")));
Assert.IsTrue(h.Accepts(Sentence.FromWords("x4")));
Assert.IsTrue(h.Accepts(Sentence.FromWords("x4 x0 x4")));
}
public void TestMissingStart01()
{
var productions = new List <Production> {
CFGParser.Production(@"<X_0> -> <X_0> <X_0>"),
CFGParser.Production(@"<X_0> -> 'a'"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("S"));
CNFGrammar h = g.ToCNF();
}
public void TestMissingStart02()
{
var productions = new List <Production> {
CFGParser.Production(@"<X_0> -> 'a'"),
};
CNFGrammar h = new CNFGrammar(productions, Nonterminal.Of("S"));
Helpers.IsNear(0.0, h.Cyk(Sentence.FromLetters("a")));
}
public void TestProduceToDepth()
{
var g = new CNFGrammar(
Enumerable.Empty <Production>(),
Nonterminal.Of("S")
);
Assert.IsTrue(g.ProduceToDepth(1).Count == 0);
Assert.IsTrue(g.ProduceToDepth(2).Count == 0);
}
public void TestToCNF06()
{
Grammar g = new Grammar(new List <Production> {
CFGParser.Production("<S> → ε"),
CFGParser.Production("<S> → 'x' <A>")
}, Nonterminal.Of("S"));
CNFGrammar h = g.ToCNF();
Helpers.AssertNear(1.0, h.Cyk(Sentence.FromWords("")));
}
public void TestFreshNames()
{
var productions = new List <Production> {
CFGParser.Production(@"<S> -> 'a'"),
CFGParser.Production(@"<X_0> -> 'b'"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("S"));
CNFGrammar h = g.ToCNF();
Assert.IsTrue(h.Accepts(Sentence.FromLetters("a")));
Assert.IsFalse(h.Accepts(Sentence.FromLetters("b")));
}
public void TestAccepts09()
{
var productions = new HashSet <Production> {
CFGParser.Production("<S> -> ε"),
// CFGParser.Production("<S> -> 'x'"),
CFGParser.Production("<S> -> <S> <S> <S>"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("S"));
CNFGrammar h = g.ToCNF();
Assert.IsTrue(h.Accepts(Sentence.FromLetters("")));
}
public void TestToCNF01()
{
var productions = new List <Production> {
CFGParser.Production(@"<X_0> -> 'x3' <X_0> [23]"),
CFGParser.Production(@"<X_0> -> ε [85]"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("X_0"));
CNFGrammar h = g.ToCNF();
Helpers.AssertNear(85.0 / 108.0, h.Cyk(Sentence.FromLetters("")));
Helpers.AssertNear((23.0 / 108.0) * (85.0 / 108.0), h.Cyk(Sentence.FromWords("x3")));
Helpers.AssertNear((23.0 / 108.0) * (23.0 / 108.0) * (85.0 / 108.0), h.Cyk(Sentence.FromWords("x3 x3")));
}
private static void ExecuteTest(Grammar g, List <Sentence> sentences)
{
CNFGrammar h = g.ToCNF();
var earley = new EarleyParser(g);
var cyk = new CykParser(h);
foreach (var sentence in sentences)
{
var p1 = cyk.ParseGetProbability(sentence);
var p2 = earley.ParseGetProbability(sentence);
Helpers.AssertNear(p1, p2);
}
}
public void TestCNFNoNull02()
{
var productions = new HashSet <Production> {
CFGParser.Production("<A> -> <A>"),
CFGParser.Production("<A> -> 'a'"),
CFGParser.Production("<A> -> 'b'"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("A"));
CNFGrammar h = g.ToCNF();
Helpers.AssertNear(0, h.Cyk(Sentence.FromLetters("")));
Helpers.AssertNear(0.5, h.Cyk(Sentence.FromLetters("a")));
Helpers.AssertNear(0.5, h.Cyk(Sentence.FromLetters("b")));
}
public void TestUnitProductions01()
{
var productions = new List <Production> {
CFGParser.Production(@"<S> -> <A> [3]"),
CFGParser.Production(@"<S> -> <B> [1]"),
CFGParser.Production(@"<A> -> 'a'"),
CFGParser.Production(@"<B> -> 'b'"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("S"));
CNFGrammar h = g.ToCNF();
Helpers.AssertNear(0.0, h.Cyk(Sentence.FromLetters("")));
Helpers.AssertNear(0.75, h.Cyk(Sentence.FromLetters("a")));
Helpers.AssertNear(0.25, h.Cyk(Sentence.FromLetters("b")));
}
public void TestAccepts02()
{
var productions = new HashSet <Production> {
CFGParser.Production("<X_0> -> <X_0> 'x4' <X_0> 'x0'"),
CFGParser.Production("<X_0> -> <X_0> <X_0> 'x2' <X_0> 'x3'"),
CFGParser.Production("<X_0> -> <X_0> 'x1' <X_0>"),
CFGParser.Production("<X_0> -> <X_0> 'x1' 'x1' 'x1' 'x3'"),
CFGParser.Production("<X_0> -> ε"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("X_0"));
CNFGrammar h = g.ToCNF();
Assert.IsTrue(h.Accepts(Sentence.FromLetters("")));
Assert.IsTrue(h.Accepts(Sentence.FromWords("x4 x0")));
Assert.IsTrue(h.Accepts(Sentence.FromWords("x4 x0 x4 x2 x3 x0")));
}
public void TestHugeWeights()
{
var productions = new List <Production> {
CFGParser.Production(@"<S> -> <A> <B> [3000000000]"),
CFGParser.Production(@"<S> -> <C> <A> [3000000000]"),
CFGParser.Production(@"<S> -> ε [3000000000]"),
CFGParser.Production(@"<A> -> 'a'"),
CFGParser.Production(@"<B> -> 'b'"),
CFGParser.Production(@"<C> -> 'c'"),
};
var g = new CNFGrammar(productions, Nonterminal.Of("S"));
Helpers.AssertNear(1.0 / 3.0, g.Cyk(Sentence.FromLetters("")));
Helpers.AssertNear(1.0 / 3.0, g.Cyk(Sentence.FromLetters("ab")));
Helpers.AssertNear(1.0 / 3.0, g.Cyk(Sentence.FromLetters("ca")));
}
public void TestCFGToCNFBadProb01()
{
// S -> aSa | bSb | ε
var productions = new List <Production> {
CFGParser.Production(@"<S> -> 'a' <S> 'a' [1]"),
CFGParser.Production(@"<S> -> 'b' <S> 'b' [3]"),
CFGParser.Production(@"<S> -> ε [4]"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("S"));
CNFGrammar h = g.ToCNF();
Helpers.AssertNear(0.5, h.Cyk(Sentence.FromLetters("")));
Helpers.AssertNear((1.0 / 8) * 0.5, h.Cyk(Sentence.FromLetters("aa")));
Helpers.AssertNear((3.0 / 8) * 0.5, h.Cyk(Sentence.FromLetters("bb")));
Helpers.AssertNear((1.0 / 8) * (3.0 / 8) * 0.5, h.Cyk(Sentence.FromLetters("abba")));
}
public void TestToCNF05()
{
Grammar g = new Grammar(new List <Production> {
CFGParser.Production("<X_0> → 'x4' <X_4> [16.517998587115667]"),
CFGParser.Production("<X_4> → 'x3' [49.290950734303777]"),
CFGParser.Production("<X_0> → 'x4' 'x1' [23.628313965456705]")
}, Nonterminal.Of("X_0"));
CNFGrammar h = g.ToCNF();
var first = 16.517998587115667;
var third = 23.628313965456705;
var sum = first + third;
Helpers.AssertNear(third / sum, h.Cyk(Sentence.FromWords("x4 x1")));
Helpers.AssertNear(first / sum, h.Cyk(Sentence.FromWords("x4 x3")));
}
public void TestToCNF04()
{
var productions = new HashSet <Production> {
CFGParser.Production("<A> -> <A> <B>"),
CFGParser.Production("<A> -> ε"),
CFGParser.Production("<B> -> 'b'"),
CFGParser.Production("<B> -> ε"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("A"));
CNFGrammar h = g.ToCNF();
var third = 1.0 / 3.0;
Helpers.AssertNear(0.5 + third * 0.5, h.Cyk(Sentence.FromLetters("")));
Helpers.AssertNear(third * 2.0 / 3.0, h.Cyk(Sentence.FromLetters("b")));
}
public void TestToCNF02()
{
var productions = new List <Production> {
CFGParser.Production(@"<S> -> 'a' <B> <B>"),
CFGParser.Production(@"<B> -> 'b'"),
CFGParser.Production(@"<B> -> ε"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("S"));
CNFGrammar h = g.ToCNF();
var pa = h.Cyk(Sentence.FromLetters("a"));
var pab = h.Cyk(Sentence.FromLetters("ab"));
var pabb = h.Cyk(Sentence.FromLetters("abb"));
Assert.IsTrue(pa > 0.0);
Assert.IsTrue(pab > 0.0);
Assert.IsTrue(pabb > 0.0);
Helpers.AssertNear(1.0, pa + pab + pabb);
}
public void TestToCNF07()
{
Grammar g = new Grammar(new List <Production> {
CFGParser.Production("<X_0> → 'x1' 'x4' <X_2> <X_6> [48.024797111295534]"),
CFGParser.Production("<X_1> → <X_0> 'x0' [28.859845304796398]"),
CFGParser.Production("<X_4> → 'x4' 'x4' 'x4' <X_3> <X_6> [32.396577754708275]"),
CFGParser.Production("<X_4> → ε [46.519217869974312]"),
CFGParser.Production("<X_0> → 'x4' 'x0' 'x3' 'x3' [90.918005973993814]"),
CFGParser.Production("<X_6> → <X_4> <X_0> 'x3' <X_3> [31.319837867431264]"),
CFGParser.Production("<X_2> → <X_2> [72.917730323932]"),
CFGParser.Production("<X_3> → <X_1> [36.901735786302822]"),
CFGParser.Production("<X_6> → ε [40.092343899464396]"),
CFGParser.Production("<X_2> → 'x1' [16.801839537826293]"),
CFGParser.Production("<X_0> → ε [136.892430380868]")
}, Nonterminal.Of("X_0"));
CNFGrammar h = g.ToCNF();
// Helpers.AssertNear(1.0, h.Cyk(Sentence.FromWords("")));
}
public void TestCYK01()
{
var productions = new List <Production> {
new Production(
Nonterminal.Of("S"),
new Sentence {
Nonterminal.Of("X"), Nonterminal.Of("X")
},
2
),
new Production(
Nonterminal.Of("X"),
new Sentence {
Nonterminal.Of("X"), Nonterminal.Of("X")
},
2
),
new Production(
Nonterminal.Of("S"),
new Sentence {
Terminal.Of("a")
},
8
),
new Production(
Nonterminal.Of("X"),
new Sentence {
Terminal.Of("a")
},
8
)
};
var g = new CNFGrammar(productions, Nonterminal.Of("S"));
Helpers.AssertNear(0.8, g.Cyk(Sentence.FromLetters("a")));
Helpers.AssertNear(0.128, g.Cyk(Sentence.FromLetters("aa")));
Helpers.AssertNear(0.04096, g.Cyk(Sentence.FromLetters("aaa")));
Helpers.AssertNear(0.016384, g.Cyk(Sentence.FromLetters("aaaa")));
Helpers.AssertNear(0.007340032, g.Cyk(Sentence.FromLetters("aaaaa")));
}
public void TestToCNF03()
{
var productions = new HashSet <Production> {
CFGParser.Production("<A> -> <B> <C>"),
CFGParser.Production("<B> -> <C>"),
CFGParser.Production("<B> -> 'b'"),
CFGParser.Production("<B> -> ε"),
CFGParser.Production("<C> -> <B>"),
CFGParser.Production("<C> -> 'c'"),
CFGParser.Production("<C> -> ε"),
};
Grammar g = new Grammar(productions, Nonterminal.Of("A"));
CNFGrammar h = g.ToCNF();
Helpers.AssertNear(0.25, h.Cyk(Sentence.FromLetters("")));
Helpers.AssertNear(0.25, h.Cyk(Sentence.FromLetters("b")));
Helpers.AssertNear(0.25, h.Cyk(Sentence.FromLetters("c")));
Helpers.AssertNear(0.140625, h.Cyk(Sentence.FromLetters("bc")));
Helpers.AssertNear(0.046875, h.Cyk(Sentence.FromLetters("cc")));
Helpers.AssertNear(0.046875, h.Cyk(Sentence.FromLetters("bb")));
Helpers.AssertNear(0.015625, h.Cyk(Sentence.FromLetters("cb")));
}
public CykParser(CNFGrammar grammar)
{
_grammar = grammar;
}
public CykParser(CNFGrammar grammar) {
_grammar = grammar;
}
