Finding Local Maxima Over a Dynamic Range

Question

Working in C#, I need to find all local peaks in a List of doubles and return them as another List doubles. This seems simple enough if I have a set number of values I\'m co

Answer 1

This function is O(n). It yields the results as it goes so it will also have very low memory overhead.

    public static IEnumerable FindPeaks(IEnumerable values, int rangeOfPeaks)
    {
        double peak = 0;
        int decay = 0;

        foreach (var value in values)
        {
            if (value > peak || decay > rangeOfPeaks / 2)
            {
                peak = value;
                decay = 0;
            }
            else
            {
                decay++;
            }

            if (decay == rangeOfPeaks / 2)
                yield return peak;
        }
    }