Question

This is probably very simple, but my attempts (guided by Intellisense and MSDN) have all been off the mark.

If I have a class which contains 3 double, how can I get the average of a list of these?

class DataPoint
{
    public int time;
    public int X;
    public int Y;
    public int Z;
    // Constructor omitted
}

class Main
{
    List<DataPoint> points = new List<DataPoint>();
    // Populate list
    DataPoint averagePoint = points.Average(someMagicHere);
}

I want averagePoint to contain time, x, y & z values that are the average of these properties of the elements that make up the list. How do I do this? The bit I’m struggling with is (I think) someMagicHere, but I could be using completely the wrong approach to begin with.

Answer 1

static class DataPointExtensions
{
 public static DataPoint Average (this IEnumerable<DataPoint> points)
 {
   int sumX=0, sumY=0, sumZ=0, count=0;
   foreach (var pt in points)
   {
      sumX += pt.X;
      sumY += pt.Y;
      sumZ += pt.Z;
      count++;
   }
   // also calc average time?
   if (count == 0)
     return new DataPoint ();
   return new DataPoint {X=sumX/count,Y=sumY/count,Z=sumZ/count};
 }
}