moving max

using System.Collections.Generic;

namespace yield
{
    public static class MovingMaxTask
    {
        public static IEnumerable<DataPoint> MovingMax(this IEnumerable<DataPoint> data, int windowWidth)
        {
            var i = 0;
            var max = 0.0;

            foreach (var point in data)
            {
                if (i < windowWidth)
                {
                    if (max < point.OriginalY)
                        max = point.OriginalY;
                    i++;
                }
                else
                {
                    max = point.OriginalY;
                    i = 0;
                }
                point.MaxY = max;
                yield return point;
            }
        }
    }
}