Project Description

This is my collection of algorithms. Migrate from CodePlex

Features

1. Extend your .NET language

Chaow.Extensions contains several extensions for array, list, date, int, string and more. You can use the extensions to make you code easier.

var matchQuery = new {
    BirthDate = 1.January(2000),    //Create date easily
    Iam = Sex.Man,
    LookingFor = Array.Enum<Sex>(), //Looking for Man, and Woman! (Expand enum)
    AgeRange = 18.To(25)            //Create number range
}

You will also be able to write Functional Programming and Dynamic Programming.

Func<int, int> fibo = null;
fibo = x => fibo(x - 1) + fibo(x - 2);
fibo = fibo.When(x => x <= 1, x => x); //Able to do pattern matching
fibo = fibo.Memoize();                 //Allow you to do memoization
var result = fibo(38);

2. Set of based class libraries

With Chaow.Numeric, you will get several new based classes for using in your code.

var prime = new Prime();
var isPrime = prime.Contains(142857); //Test for prime number
var primeList = prime.Take(10000);    //Generate prime numbers

3. Solve polynomial problems

You can easily analyze your math functions with Chaow.Numeric2.

ie. Solve integer of X, Y in {"3XX + 14XY + 6YY - 17X - 23Y - 505 = 0"}

var solutions = Diophantine.Parse((x, y) => 3 * x * x + 14 * x * y + 6 * y * y - 17 * x - 23 * y - 505).Solutions;
var x = solutions[0].X0;
var y = solutions[0].Y0;

ie2. Find formula from sequence of numbers

var formula = MathExt2.PolynomialInterpolation(new Rational[] { 1, 8, 27, 64 });
Console.WriteLine(formula.Rewrite());
//Output is x => x.Power(3)

4. Solve nonpolynomial problems

Chaow.Combinatorics will allow you to backtrack with any types of problem.

ie. Solve 8 Queens easily, with few lines of code.

var solutions = "ABCDEFGH".Backtrack(8);
solutions.BacktrackingModel = BacktrackingModel.Permutation;
solutions.AppendConstraint(set => q =>
    set.All((x, i) => (set.Length - i != (x - q).Abs()))
);
var answer = solutions.First();

Finally, may I introduce new language LINCON (Language INtegrated CONstraint programming). LINCON is strong type constraint programming, which fast, declarative style and fun!

ie3. Solving Einstein's puzzle with LINCON!

var solutions = from n in ArrayExt.Enum<Nationality>().ToConstraintList(5)
                from c in ArrayExt.Enum<HouseColor>().ToConstraintList(5)
                from s in ArrayExt.Enum<Smoke>().ToConstraintList(5)
                from d in ArrayExt.Enum<Drink>().ToConstraintList(5)
                from p in ArrayExt.Enum<Pet>().ToConstraintList(5)

                from i in 0.To(4).ToConstraintIndex()

                where Constraint.AllDifferent(n)
                where Constraint.AllDifferent(c)
                where Constraint.AllDifferent(s)
                where Constraint.AllDifferent(d)
                where Constraint.AllDifferent(p)

                where n[0] == Nationality.Norwegian
                where d[2] == Drink.Milk
                where (n[i] == Nationality.British) == (c[i] == HouseColor.Red)
                where (n[i] == Nationality.German) == (s[i] == Smoke.Prince)
                where (c[i] == HouseColor.Yellow) == (s[i] == Smoke.DunHill)
                where (n[i] == Nationality.Danish) == (d[i] == Drink.Tea)
                where (c[i] == HouseColor.Green) == (d[i] == Drink.Coffee)
                where (s[i] == Smoke.BlueMaster) == (d[i] == Drink.Beer)
                where (n[i] == Nationality.Swedish) == (p[i] == Pet.Dog)
                where (s[i] == Smoke.PallMall) == (p[i] == Pet.Bird)

                where (c[i] == HouseColor.Green) == (c[i + 1] == HouseColor.White)
                where (p[i] == Pet.Cat) ? (s[i - 1] == Smoke.Blend || s[i + 1] == Smoke.Blend) : true
                where ((p[i] == Pet.Horse) ? (s[i - 1] == Smoke.DunHill || s[i + 1] == Smoke.DunHill) : true)
                where ((n[i] == Nationality.Norwegian) ? (c[i - 1] == HouseColor.Blue || c[i + 1] == HouseColor.Blue) : true) 
                where ((s[i] == Smoke.Blend) ? (d[i - 1] == Drink.Water || d[i + 1] == Drink.Water) : true) 

                select 0.To(4).Select(x =>
                    new {
                        Nationality = n[x],
                        HouseColor = c[x],
                        Smoke = s[x],
                        Drink = d[x],
                        Pet = p[x]
                    });
var answer = solutions.First();

Modules

module	description
Chaow.Algorithms	provides data type to solve specific problems ie. binary indexed tree disjoint set, hungarian algorithm
Chaow.Combinatorics	enables you to do combinatoric search easier ie. combination, permutation, partition
Chaow.Expression	enhances the power of expression ie. exp matcher, exp replacer, exp rewriter
Chaow.Extensions	extends .NET framework types ie. int, string, ienumerable, func
Chaow.LINCON	language integrated constraint programming, allows you to write cp with linq
Chaow.Numeric	provides various high performance numeric types ie. prime, biginteger, rational
Chaow.Numeric 2	allows you to do mathematical analysis ie. diophantine solver, polynomial rewriter

chaowlert / algorithm