jvangael
17 years ago
committed by
Christoph Ruegg
Christoph Ruegg
7 changed files with 746 additions and 2 deletions
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// <copyright file="SortingTests.cs" company="Math.NET">
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// Math.NET Numerics, part of the Math.NET Project
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// http://mathnet.opensourcedotnet.info
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//
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// Copyright (c) 2009 Math.NET
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//
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// Permission is hereby granted, free of charge, to any person
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// obtaining a copy of this software and associated documentation
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// files (the "Software"), to deal in the Software without
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// restriction, including without limitation the rights to use,
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// copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the
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// Software is furnished to do so, subject to the following
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// conditions:
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//
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// The above copyright notice and this permission notice shall be
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// included in all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
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// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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// OTHER DEALINGS IN THE SOFTWARE.
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// </copyright>
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namespace MathNet.Numerics.UnitTests |
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{ |
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using System; |
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using System.Collections.Generic; |
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using System.Text; |
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using MbUnit.Framework; |
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using MathNet.Numerics; |
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[TestFixture] |
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public class SortingTests |
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{ |
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[Test] |
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public void TestRandomTupleArraySorting() |
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{ |
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const int Len = 0x1 << 10; |
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var random = new Random(); |
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int[] keys = new int[Len]; |
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int[] items = new int[Len]; |
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int[] keysCopy = new int[Len]; |
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for(int i = 0; i < keys.Length; i++) |
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{ |
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keys[i] = random.Next(); |
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keysCopy[i] = keys[i]; |
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items[i] = -keys[i]; |
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} |
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Sorting.Sort(keys, items); |
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for(int i = 1; i < keys.Length; i++) |
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{ |
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Assert.IsTrue(keys[i] >= keys[i - 1], "Sort Order - " + i.ToString()); |
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Assert.AreEqual(items[i], -keys[i], "Items Permutation - " + i.ToString()); |
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} |
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for(int i = 0; i < keysCopy.Length; i++) |
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{ |
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Assert.IsTrue(Array.IndexOf(keys, keysCopy[i]) >= 0, "All keys still there - " + i.ToString()); |
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} |
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} |
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[Test] |
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public void TestRandomTupleListSorting() |
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{ |
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const int Len = 0x1 << 10; |
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var random = new Random(); |
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List<int> keys = new List<int>(Len); |
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List<int> items = new List<int>(Len); |
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int[] keysCopy = new int[Len]; |
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for(int i = 0; i < Len; i++) |
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{ |
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int value = random.Next(); |
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keys.Add(value); |
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keysCopy[i] = value; |
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items.Add(-value); |
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} |
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Sorting.Sort(keys, items); |
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for(int i = 1; i < Len; i++) |
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{ |
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Assert.IsTrue(keys[i] >= keys[i - 1], "Sort Order - " + i.ToString()); |
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Assert.AreEqual(items[i], -keys[i], "Items Permutation - " + i.ToString()); |
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} |
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for(int i = 0; i < keysCopy.Length; i++) |
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{ |
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Assert.IsTrue(keys.IndexOf(keysCopy[i]) >= 0, "All keys still there - " + i.ToString()); |
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} |
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} |
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[Test] |
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public void TestRandomTripleArraySorting() |
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{ |
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const int Len = 0x1 << 10; |
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var random = new Random(); |
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int[] keys = new int[Len]; |
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int[] items1 = new int[Len]; |
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int[] items2 = new int[Len]; |
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int[] keysCopy = new int[Len]; |
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for(int i = 0; i < keys.Length; i++) |
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{ |
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keys[i] = random.Next(); |
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keysCopy[i] = keys[i]; |
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items1[i] = -keys[i]; |
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items2[i] = keys[i] >> 2; |
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} |
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Sorting.Sort(keys, items1, items2); |
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for(int i = 1; i < keys.Length; i++) |
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{ |
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Assert.IsTrue(keys[i] >= keys[i - 1], "Sort Order - " + i.ToString()); |
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Assert.AreEqual(items1[i], -keys[i], "Items1 Permutation - " + i.ToString()); |
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Assert.AreEqual(items2[i], keys[i] >> 2, "Items2 Permutation - " + i.ToString()); |
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} |
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for(int i = 0; i < keysCopy.Length; i++) |
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{ |
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Assert.IsTrue(Array.IndexOf(keys, keysCopy[i]) >= 0, "All keys still there - " + i.ToString()); |
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} |
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} |
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[Test] |
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public void TestAppliedListSorting() |
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{ |
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const int Len = 0x1 << 10; |
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var random = new Random(); |
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List<int> list = new List<int>(); |
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for(int i = 0; i < Len; i++) |
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{ |
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list.Add(random.Next()); |
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} |
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// default sorting (Ascending)
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list.Sort(); |
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// just check that the order is as expected, not that the items are correct
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for(int i = 1; i < list.Count; i++) |
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{ |
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Assert.IsTrue(list[i] >= list[i - 1], "Sort Order - " + i.ToString()); |
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} |
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} |
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} |
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} |
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@ -0,0 +1,574 @@ |
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// <copyright file="Sorting.cs" company="Math.NET">
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// Math.NET Numerics, part of the Math.NET Project
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// http://mathnet.opensourcedotnet.info
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//
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// Copyright (c) 2009 Math.NET
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//
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// Permission is hereby granted, free of charge, to any person
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// obtaining a copy of this software and associated documentation
|
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// files (the "Software"), to deal in the Software without
|
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// restriction, including without limitation the rights to use,
|
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// copy, modify, merge, publish, distribute, sublicense, and/or sell
|
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// copies of the Software, and to permit persons to whom the
|
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// Software is furnished to do so, subject to the following
|
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// conditions:
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//
|
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// The above copyright notice and this permission notice shall be
|
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// included in all copies or substantial portions of the Software.
|
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//
|
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
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// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
|
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// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
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// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
|
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// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
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// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
|
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// OTHER DEALINGS IN THE SOFTWARE.
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// </copyright>
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namespace MathNet.Numerics |
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{ |
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using System; |
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using System.Collections.Generic; |
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using System.Text; |
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/// <summary>
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/// Sorting algorithms for single, tuple and triple lists.
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/// </summary>
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public static class Sorting |
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{ |
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/// <summary>
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/// Sort a list of keys, inplace using the quick sort algorithm.
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/// </summary>
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/// <typeparam name="T">The type of elements stored in the list.</typeparam>
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/// <param name="keys">List to sort.</param>
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public static void Sort<T>(IList<T> keys) |
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{ |
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Sort(keys, Comparer<T>.Default); |
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} |
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/// <summary>
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/// Sort a list of keys and items with respect to the keys, inplace using the quick sort algorithm.
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/// </summary>
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/// <typeparam name="TKey">The type of elements stored in the key list.</typeparam>
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/// <typeparam name="TItem">The type of elements stored in the item list.</typeparam>
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/// <param name="keys">List to sort.</param>
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/// <param name="items">List to permutate the same way as the key list.</param>
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public static void Sort<TKey, TItem>(IList<TKey> keys, IList<TItem> items) |
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{ |
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Sort(keys, items, Comparer<TKey>.Default); |
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} |
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/// <summary>
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/// Sort a list of keys, items1 and items2 with respect to the keys, inplace using the quick sort algorithm.
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/// </summary>
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/// <typeparam name="TKey">The type of elements stored in the key list.</typeparam>
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/// <typeparam name="TItem1">The type of elements stored in the first item list.</typeparam>
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/// <typeparam name="TItem2">The type of elements stored in the second item list.</typeparam>
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/// <param name="keys">List to sort.</param>
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/// <param name="items1">First list to permutate the same way as the key list.</param>
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/// <param name="items2">Second list to permutate the same way as the key list.</param>
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public static void Sort<TKey, TItem1, TItem2>(IList<TKey> keys, IList<TItem1> items1, IList<TItem2> items2) |
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{ |
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Sort(keys, items1, items2, Comparer<TKey>.Default); |
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} |
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/// <summary>
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/// Sort a range of a list of keys, inplace using the quick sort algorithm.
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/// </summary>
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/// <typeparam name="T">The type of elements in the key list.</typeparam>
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/// <param name="keys">List to sort.</param>
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/// <param name="index">The zero-based starting index of the range to sort.</param>
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/// <param name="count">The length of the range to sort.</param>
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public static void Sort<T>(IList<T> keys, int index, int count) |
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{ |
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Sort(keys, index, count, Comparer<T>.Default); |
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} |
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/// <summary>
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/// Sort a list of keys, inplace using the quick sort algorithm using the quick sort algorithm.
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/// </summary>
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/// <typeparam name="T">The type of elements in the key list.</typeparam>
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/// <param name="keys">List to sort.</param>
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/// <param name="comparer">Comparison, defining the sort order.</param>
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public static void Sort<T>(IList<T> keys, IComparer<T> comparer) |
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{ |
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if(null == keys) |
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{ |
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throw new ArgumentNullException("keys"); |
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} |
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if(null == comparer) |
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{ |
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throw new ArgumentNullException("comparer"); |
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} |
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// basic cases
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if(keys.Count <= 1) |
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{ |
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return; |
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} |
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if(keys.Count == 2) |
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{ |
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if(comparer.Compare(keys[0], keys[1]) > 0) |
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{ |
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Swap(keys, 0, 1); |
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} |
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return; |
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} |
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// generic list case
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List<T> list = keys as List<T>; |
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if(null != list) |
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{ |
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list.Sort(comparer); |
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return; |
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} |
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// array case
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T[] array = keys as T[]; |
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if(null != array) |
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{ |
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Array.Sort(array, comparer); |
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return; |
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} |
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// local sort implementation
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QuickSort(keys, comparer, 0, keys.Count - 1); |
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} |
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/// <summary>
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/// Sort a list of keys and items with respect to the keys, inplace using the quick sort algorithm.
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/// </summary>
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/// <typeparam name="TKey">The type of elements in the key list.</typeparam>
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/// <typeparam name="TItem">The type of elements in the item list.</typeparam>
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/// <param name="keys">List to sort.</param>
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/// <param name="items">List to permutate the same way as the key list.</param>
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/// <param name="comparer">Comparison, defining the sort order.</param>
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public static void Sort<TKey, TItem>(IList<TKey> keys, IList<TItem> items, IComparer<TKey> comparer) |
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{ |
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if(null == keys) |
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{ |
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throw new ArgumentNullException("keys"); |
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} |
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if(null == items) |
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{ |
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throw new ArgumentNullException("items"); |
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} |
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if(null == comparer) |
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{ |
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throw new ArgumentNullException("comparer"); |
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} |
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// array case
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TKey[] keysArray = keys as TKey[]; |
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TItem[] itemsArray = items as TItem[]; |
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if((null != keysArray) && (null != itemsArray)) |
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{ |
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Array.Sort(keysArray, itemsArray, comparer); |
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return; |
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} |
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// local sort implementation
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QuickSort(keys, items, comparer, 0, keys.Count - 1); |
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} |
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/// <summary>
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/// Sort a list of keys, items1 and items2 with respect to the keys, inplace using the quick sort algorithm.
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/// </summary>
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/// <typeparam name="TKey">The type of elements in the key list.</typeparam>
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/// <typeparam name="TItem1">The type of elements in the first item list.</typeparam>
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/// <typeparam name="TItem2">The type of elements in the second item list.</typeparam>
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/// <param name="keys">List to sort.</param>
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/// <param name="items1">First list to permutate the same way as the key list.</param>
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/// <param name="items2">Second list to permutate the same way as the key list.</param>
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/// <param name="comparer">Comparison, defining the sort order.</param>
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public static void Sort<TKey, TItem1, TItem2>( |
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IList<TKey> keys, IList<TItem1> items1, IList<TItem2> items2, IComparer<TKey> comparer) |
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{ |
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if(null == keys) |
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{ |
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throw new ArgumentNullException("keys"); |
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} |
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if(null == items1) |
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{ |
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throw new ArgumentNullException("items1"); |
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} |
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if(null == items2) |
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{ |
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throw new ArgumentNullException("items2"); |
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} |
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if(null == comparer) |
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{ |
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throw new ArgumentNullException("comparer"); |
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} |
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// local sort implementation
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QuickSort(keys, items1, items2, comparer, 0, keys.Count - 1); |
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} |
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/// <summary>
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/// Sort a range of a list of keys, inplace using the quick sort algorithm.
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/// </summary>
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/// <typeparam name="T">The type of element in the list.</typeparam>
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/// <param name="keys">List to sort.</param>
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/// <param name="index">The zero-based starting index of the range to sort.</param>
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/// <param name="count">The length of the range to sort.</param>
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/// <param name="comparer">Comparison, defining the sort order.</param>
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public static void Sort<T>(IList<T> keys, int index, int count, IComparer<T> comparer) |
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{ |
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if(null == keys) |
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{ |
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throw new ArgumentNullException("keys"); |
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} |
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if(null == comparer) |
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{ |
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throw new ArgumentNullException("comparer"); |
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} |
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if(index < 0 || index >= keys.Count) |
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{ |
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throw new ArgumentOutOfRangeException("index"); |
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} |
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if(count < 0 || index + count > keys.Count) |
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{ |
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throw new ArgumentOutOfRangeException("count"); |
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} |
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// basic cases
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if(count <= 1) |
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{ |
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return; |
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} |
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if(count == 2) |
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{ |
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if(comparer.Compare(keys[index], keys[index + 1]) > 0) |
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{ |
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Swap(keys, index, index + 1); |
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} |
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return; |
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} |
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// generic list case
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List<T> list = keys as List<T>; |
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if(null != list) |
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{ |
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list.Sort(index, count, comparer); |
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return; |
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} |
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// array case
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T[] array = keys as T[]; |
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if(null != array) |
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{ |
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Array.Sort(array, index, count, comparer); |
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return; |
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} |
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// local sort implementation
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QuickSort(keys, comparer, index, count - 1); |
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} |
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/// <summary>
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/// Recursive implementation for an inplace quick sort on a list.
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/// </summary>
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/// <typeparam name="T">The type of the list on which the quick sort is performed.</typeparam>
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/// <param name="keys">The list which is sorted using quick sort.</param>
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/// <param name="comparer">The method with which to compare two elements of the quick sort.</param>
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/// <param name="left">The left boundary of the quick sort.</param>
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/// <param name="right">The right boundary of the quick sort.</param>
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private static void QuickSort<T>(IList<T> keys, IComparer<T> comparer, int left, int right) |
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{ |
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do |
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{ |
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// Pivoting
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int a = left; |
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int b = right; |
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int p = a + ((b - a) >> 1); // midpoint
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if(comparer.Compare(keys[a], keys[p]) > 0) |
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{ |
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Swap(keys, a, p); |
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} |
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if(comparer.Compare(keys[a], keys[b]) > 0) |
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{ |
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Swap(keys, a, b); |
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} |
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if(comparer.Compare(keys[p], keys[b]) > 0) |
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{ |
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Swap(keys, p, b); |
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} |
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T pivot = keys[p]; |
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// Hoare Partitioning
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do |
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{ |
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while(comparer.Compare(keys[a], pivot) < 0) |
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{ |
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a++; |
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} |
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while(comparer.Compare(pivot, keys[b]) < 0) |
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{ |
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b--; |
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} |
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if(a > b) |
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{ |
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break; |
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} |
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if(a < b) |
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{ |
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Swap(keys, a, b); |
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} |
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a++; |
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b--; |
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} |
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while(a <= b); |
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// In order to limit the recusion depth to log(n), we sort the
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// shorter partition recusively and the longer partition iteratively.
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if((b - left) <= (right - a)) |
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{ |
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if(left < b) |
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{ |
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QuickSort(keys, comparer, left, b); |
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} |
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left = a; |
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} |
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else |
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{ |
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if(a < right) |
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{ |
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QuickSort(keys, comparer, a, right); |
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} |
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right = b; |
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} |
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} |
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while(left < right); |
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} |
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/// <summary>
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/// Recursive implementation for an inplace quick sort on a list while reordering one other list accordingly.
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/// </summary>
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/// <typeparam name="T">The type of the list on which the quick sort is performed.</typeparam>
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/// <typeparam name="TItems">The type of the list which is automatically reordered accordingly.</typeparam>
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/// <param name="keys">The list which is sorted using quick sort.</param>
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/// <param name="items">The list which is automatically reordered accordingly.</param>
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/// <param name="comparer">The method with which to compare two elements of the quick sort.</param>
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/// <param name="left">The left boundary of the quick sort.</param>
|
|||
/// <param name="right">The right boundary of the quick sort.</param>
|
|||
private static void QuickSort<T, TItems>(IList<T> keys, IList<TItems> items, IComparer<T> comparer, int left, int right) |
|||
{ |
|||
do |
|||
{ |
|||
// Pivoting
|
|||
int a = left; |
|||
int b = right; |
|||
int p = a + ((b - a) >> 1); // midpoint
|
|||
|
|||
if(comparer.Compare(keys[a], keys[p]) > 0) |
|||
{ |
|||
Swap(keys, a, p); |
|||
Swap(items, a, p); |
|||
} |
|||
|
|||
if(comparer.Compare(keys[a], keys[b]) > 0) |
|||
{ |
|||
Swap(keys, a, b); |
|||
Swap(items, a, b); |
|||
} |
|||
|
|||
if(comparer.Compare(keys[p], keys[b]) > 0) |
|||
{ |
|||
Swap(keys, p, b); |
|||
Swap(items, p, b); |
|||
} |
|||
|
|||
T pivot = keys[p]; |
|||
|
|||
// Hoare Partitioning
|
|||
do |
|||
{ |
|||
while(comparer.Compare(keys[a], pivot) < 0) |
|||
{ |
|||
a++; |
|||
} |
|||
|
|||
while(comparer.Compare(pivot, keys[b]) < 0) |
|||
{ |
|||
b--; |
|||
} |
|||
|
|||
if(a > b) |
|||
{ |
|||
break; |
|||
} |
|||
|
|||
if(a < b) |
|||
{ |
|||
Swap(keys, a, b); |
|||
Swap(items, a, b); |
|||
} |
|||
|
|||
a++; |
|||
b--; |
|||
} |
|||
while(a <= b); |
|||
|
|||
// In order to limit the recusion depth to log(n), we sort the
|
|||
// shorter partition recusively and the longer partition iteratively.
|
|||
if((b - left) <= (right - a)) |
|||
{ |
|||
if(left < b) |
|||
{ |
|||
QuickSort(keys, items, comparer, left, b); |
|||
} |
|||
|
|||
left = a; |
|||
} |
|||
else |
|||
{ |
|||
if(a < right) |
|||
{ |
|||
QuickSort(keys, items, comparer, a, right); |
|||
} |
|||
|
|||
right = b; |
|||
} |
|||
} |
|||
while(left < right); |
|||
} |
|||
|
|||
/// <summary>
|
|||
/// Recursive implementation for an inplace quick sort on one list while reordering two other lists accordingly.
|
|||
/// </summary>
|
|||
/// <typeparam name="T">The type of the list on which the quick sort is performed.</typeparam>
|
|||
/// <typeparam name="TItems1">The type of the first list which is automatically reordered accordingly.</typeparam>
|
|||
/// <typeparam name="TItems2">The type of the second list which is automatically reordered accordingly.</typeparam>
|
|||
/// <param name="keys">The list which is sorted using quick sort.</param>
|
|||
/// <param name="items1">The first list which is automatically reordered accordingly.</param>
|
|||
/// <param name="items2">The second list which is automatically reordered accordingly.</param>
|
|||
/// <param name="comparer">The method with which to compare two elements of the quick sort.</param>
|
|||
/// <param name="left">The left boundary of the quick sort.</param>
|
|||
/// <param name="right">The right boundary of the quick sort.</param>
|
|||
private static void QuickSort<T, TItems1, TItems2>( |
|||
IList<T> keys, IList<TItems1> items1, IList<TItems2> items2, IComparer<T> comparer, int left, int right) |
|||
{ |
|||
do |
|||
{ |
|||
// Pivoting
|
|||
int a = left; |
|||
int b = right; |
|||
int p = a + ((b - a) >> 1); // midpoint
|
|||
|
|||
if(comparer.Compare(keys[a], keys[p]) > 0) |
|||
{ |
|||
Swap(keys, a, p); |
|||
Swap(items1, a, p); |
|||
Swap(items2, a, p); |
|||
} |
|||
|
|||
if(comparer.Compare(keys[a], keys[b]) > 0) |
|||
{ |
|||
Swap(keys, a, b); |
|||
Swap(items1, a, b); |
|||
Swap(items2, a, b); |
|||
} |
|||
|
|||
if(comparer.Compare(keys[p], keys[b]) > 0) |
|||
{ |
|||
Swap(keys, p, b); |
|||
Swap(items1, p, b); |
|||
Swap(items2, p, b); |
|||
} |
|||
|
|||
T pivot = keys[p]; |
|||
|
|||
// Hoare Partitioning
|
|||
do |
|||
{ |
|||
while(comparer.Compare(keys[a], pivot) < 0) |
|||
{ |
|||
a++; |
|||
} |
|||
|
|||
while(comparer.Compare(pivot, keys[b]) < 0) |
|||
{ |
|||
b--; |
|||
} |
|||
|
|||
if(a > b) |
|||
{ |
|||
break; |
|||
} |
|||
|
|||
if(a < b) |
|||
{ |
|||
Swap(keys, a, b); |
|||
Swap(items1, a, b); |
|||
Swap(items2, a, b); |
|||
} |
|||
|
|||
a++; |
|||
b--; |
|||
} |
|||
while(a <= b); |
|||
|
|||
// In order to limit the recusion depth to log(n), we sort the
|
|||
// shorter partition recusively and the longer partition iteratively.
|
|||
if((b - left) <= (right - a)) |
|||
{ |
|||
if(left < b) |
|||
{ |
|||
QuickSort(keys, items1, items2, comparer, left, b); |
|||
} |
|||
|
|||
left = a; |
|||
} |
|||
else |
|||
{ |
|||
if(a < right) |
|||
{ |
|||
QuickSort(keys, items1, items2, comparer, a, right); |
|||
} |
|||
|
|||
right = b; |
|||
} |
|||
} |
|||
while(left < right); |
|||
} |
|||
|
|||
/// <summary>
|
|||
/// Performs an in place swap of two elements in a list.
|
|||
/// </summary>
|
|||
/// <typeparam name="T">The type of elements stored in the list.</typeparam>
|
|||
/// <param name="keys">The list in which the elements are stored.</param>
|
|||
/// <param name="a">The index of the first element of the swap.</param>
|
|||
/// <param name="b">The index of the second element of the swap.</param>
|
|||
internal static void Swap<T>(IList<T> keys, int a, int b) |
|||
{ |
|||
T local = keys[a]; |
|||
keys[a] = keys[b]; |
|||
keys[b] = local; |
|||
} |
|||
} |
|||
} |
|||
Loading…
Reference in new issue