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排序数组C#的最快方法

[英]Fastest way to sort an Array c#

Hi this is my problem I have an array of points P(x,y) and I need to sort these points from the furthest to the closest, respect to the barycenter of a Polygon, this what I have done (I know this is a bad solution ) how can I do a better and aboveall faster solution? 嗨,这是我的问题,我有一个点P(x,y)的数组,我需要根据多边形的重心从最远到最近对这些点进行排序,这是我所做的(我知道这是一个糟糕的解决方案)我该如何做一个更好,更快速的解决方案?

List<C2DPoint> OrderedGripperPoints = new List<C2DPoint> { };

while(myGripperPoints.Count!=0) 
{
    double dist=-1;
    int index=-1;
    for(int k=0;k<myGripperPoints.Count;k++)
    {
        if(myGripperPoints[k].Distance(WorkScrap.GetCentroid())>=dist)
        {
            index = k;
            dist = myGripperPoints[k].Distance(WorkScrap.GetCentroid());
        }
    }

    OrderedGripperPoints.Add(myGripperPoints[index]);
    myGripperPoints.RemoveAt(index);
}

Thanks for your answers... 感谢您的回答...

Use Linq to order points. 使用Linq排序点。

using System.Linq;

var sortedList = myGripperPoints.OrderBy(p => p.Distance(WorkScrap.GetCentroid())).ToList();

Consider the following code: 考虑以下代码:

Point Class (assumed class definition) 点类(假设类定义)

class Point
{
    public int X { get; set;}

    public int Y { get; set;}   
}

Point EqualityComparer 点平等比较器

class PointEqualityComparer : IEqualityComparer<Point>
{
    public bool Equals(Point p1, Point p2) { return p1.X == p2.X && p1.Y == p2.Y; }

    public int GetHashCode(Point p) { return p.X.GetHashCode() *31 + p.Y.GetHashCode()*23; }
}

Create a Dictionary with Point as Key and Distance as value (assuming integer): 创建一个字典,将Point作为键,将Distance作为值(假设为整数):

Dictionary<Point,int> pointDictionary = 
new Dictionary<Point, int>(new PointEqualityComparer());

Add Points as follows: 添加点如下:

Point p = new Point {X = <value>, Y = <value>};
pointDictionary.Add(p,p.Distance(WorkScrap.GetCentroid()));

Order by Distance as follows: 按距离排序如下:

pointDictionary.OrderByDescending(x => x.Value).ToList();
  1. Ordering is done by Distance in Descending order as expected 按距离顺序按期望的降序排列
  2. Result would be List<KeyValuePair<Point,int>> , where elements are in Descending order 结果将是List<KeyValuePair<Point,int>> ,其中元素按降序排列

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