discrete-optimization-coursera/puzzle/magicSquare/Tests/SquareMatrixTests.cs

using System;
using System.Linq;
using NUnit.Framework;

namespace magicSquare.Tests
{
	[TestFixture]
	public class SquareMatrixTests
	{
		[Test]
		public void Init()
		{
			var vals 
				= new [,]
					{
						{1, 2, 3}, 
						{4, 5, 6}, 
						{7, 8, 9}
					};

			var matrix = new SquareMatrix(vals);
			Assert.That(matrix.IsFeasible(), Is.False);

			Assert.That(matrix.ColumnSum(0), Is.EqualTo(12));
			Assert.That(matrix.ColumnSum(1), Is.EqualTo(15));
			Assert.That(matrix.ColumnSum(2), Is.EqualTo(18));
			Assert.That(matrix.RowSum(0), Is.EqualTo(6));
			Assert.That(matrix.RowSum(1), Is.EqualTo(15));
			Assert.That(matrix.RowSum(2), Is.EqualTo(24));
			Assert.That(matrix.Diag1Sum, Is.EqualTo(15));
			Assert.That(matrix.Diag2Sum, Is.EqualTo(15));
			Assert.That(matrix.ColumnDelta(0), Is.EqualTo(-3));
			Assert.That(matrix.ColumnDelta(1), Is.EqualTo(0));
			Assert.That(matrix.ColumnDelta(2), Is.EqualTo(3));
			Assert.That(matrix.RowDelta(0), Is.EqualTo(-9));
			Assert.That(matrix.RowDelta(1), Is.EqualTo(0));
			Assert.That(matrix.RowDelta(2), Is.EqualTo(9));
		}

		[Test]
		public void Swap()
		{
			var vals 
				= new [,]
					{
						{1, 2, 3}, 
						{4, 5, 6}, 
						{7, 8, 9}
					};

			var matrix = new SquareMatrix(vals);
			matrix.Swap(1,1,2,1);
			PrintMatrix(matrix);
			Assert.That(matrix.IsFeasible(), Is.False);

			Assert.That(matrix.ColumnSum(0), Is.EqualTo(12));
			Assert.That(matrix.ColumnSum(1), Is.EqualTo(15));
			Assert.That(matrix.ColumnSum(2), Is.EqualTo(18));
			Assert.That(matrix.RowSum(0), Is.EqualTo(6));
			Assert.That(matrix.RowSum(1), Is.EqualTo(18));
			Assert.That(matrix.RowSum(2), Is.EqualTo(21));
			Assert.That(matrix.Diag1Sum, Is.EqualTo(18));
			Assert.That(matrix.Diag2Sum, Is.EqualTo(18));
			Assert.That(matrix.ColumnDelta(0), Is.EqualTo(-3));
			Assert.That(matrix.ColumnDelta(1), Is.EqualTo(0));
			Assert.That(matrix.ColumnDelta(2), Is.EqualTo(3));
			Assert.That(matrix.RowDelta(0), Is.EqualTo(-9));
			Assert.That(matrix.RowDelta(1), Is.EqualTo(3));
			Assert.That(matrix.RowDelta(2), Is.EqualTo(6));
		}

		[Test]
		public void Swap2()
		{
			var vals 
				= new [,]
					{
						{1, 2, 3}, 
						{4, 5, 6}, 
						{7, 8, 9}
					};

			var matrix = new SquareMatrix(vals);
			matrix.Swap(0,1,1,2);
			PrintMatrix(matrix);
			Assert.That(matrix.IsFeasible(), Is.False);

			Assert.That(matrix.ColumnSum(0), Is.EqualTo(12));
			Assert.That(matrix.ColumnSum(1), Is.EqualTo(19));
			Assert.That(matrix.ColumnSum(2), Is.EqualTo(14));
			Assert.That(matrix.RowSum(0), Is.EqualTo(10));
			Assert.That(matrix.RowSum(1), Is.EqualTo(11));
			Assert.That(matrix.RowSum(2), Is.EqualTo(24));
			Assert.That(matrix.Diag1Sum, Is.EqualTo(15));
			Assert.That(matrix.Diag2Sum, Is.EqualTo(15));
			Assert.That(matrix.ColumnDelta(0), Is.EqualTo(-3));
			Assert.That(matrix.ColumnDelta(1), Is.EqualTo(4));
			Assert.That(matrix.ColumnDelta(2), Is.EqualTo(-1));
			Assert.That(matrix.RowDelta(0), Is.EqualTo(-5));
			Assert.That(matrix.RowDelta(1), Is.EqualTo(-4));
			Assert.That(matrix.RowDelta(2), Is.EqualTo(9));
		}

		[Test]
		public void Swap3()
		{
			var vals 
				= new [,]
					{
						{1, 2, 3}, 
						{4, 5, 6}, 
						{7, 8, 9}
					};

			var matrix = new SquareMatrix(vals);
			matrix.Swap(2,0,1,2);
			PrintMatrix(matrix);
			Assert.That(matrix.IsFeasible(), Is.False);

			Assert.That(matrix.ColumnSum(0), Is.EqualTo(11));
			Assert.That(matrix.ColumnSum(1), Is.EqualTo(15));
			Assert.That(matrix.ColumnSum(2), Is.EqualTo(19));
			Assert.That(matrix.RowSum(0), Is.EqualTo(6));
			Assert.That(matrix.RowSum(1), Is.EqualTo(16));
			Assert.That(matrix.RowSum(2), Is.EqualTo(23));
			Assert.That(matrix.Diag1Sum, Is.EqualTo(15));
			Assert.That(matrix.Diag2Sum, Is.EqualTo(14));
			Assert.That(matrix.ColumnDelta(0), Is.EqualTo(-4));
			Assert.That(matrix.ColumnDelta(1), Is.EqualTo(0));
			Assert.That(matrix.ColumnDelta(2), Is.EqualTo(4));
			Assert.That(matrix.RowDelta(0), Is.EqualTo(-9));
			Assert.That(matrix.RowDelta(1), Is.EqualTo(1));
			Assert.That(matrix.RowDelta(2), Is.EqualTo(8));
		}

		[Test]
		public void Deltas()
		{
			var vals
				= new[,]
					{
						{1, 2, 3},
						{4, 5, 6},
						{7, 8, 9}
					};

			var matrix = new SquareMatrix(vals);
			var pairs = matrix.MaxColumnDeltaPairs().ToArray();
			Assert.That(pairs.First(), Is.EqualTo(new Tuple<int,int>(0,2)));
		}
		[Test]
		public void Deltas2()
		{
			var vals
				= new[,]
					{
						{1, 2, 3, 4},
						{4, 5, 6, 7},
						{8, 9, 10, 11},
						{12,13,14,15}
					};

			var matrix = new SquareMatrix(vals);
			var pairs = matrix.MaxColumnDeltaPairs().ToArray();
			Assert.That(pairs.First(), Is.EqualTo(new Tuple<int,int>(1,3)));
		}

		[Test]
		public void IsDiagonalTest()
		{
			var vals
				= new[,]
					{
						{1, 2, 3, 4},
						{4, 5, 6, 7},
						{8, 9, 10, 11},
						{12,13,14,15}
					};

			

		}

		private void PrintMatrix(SquareMatrix sm)
		{
			Console.WriteLine(sm.Size);
			var rowValues =
				from row in Enumerable.Range(0, sm.Size)
				let rowVals =
					(from col in Enumerable.Range(0, sm.Size)
					 select sm.GetValue(row,col))
				select rowVals;
			foreach (var rowValue in rowValues)
			{
				Console.WriteLine(string.Join("\t", rowValue.ToArray()));
			}
		}
	}
}