How do I get the index of the highest value in an array using LINQ?

Question

I have an array of doubles and I want the index of the highest value. These are the solutions that I\'ve come up with so far but I think that there must be a more elegant so

Answer 1

If you want something that looks LINQy, in that it's purely functional, then Jon Skeets' answer above can be recast as:

public static int MaxIndex(this IEnumerable sequence) where T : IComparable
    {
        return sequence.Aggregate(
            new { maxIndex = -1, maxValue = default(T), thisIndex = 0 },
            ((agg, value) => (value.CompareTo(agg.maxValue) > 0 || agg.maxIndex == -1) ?
                             new {maxIndex = agg.thisIndex, maxValue = value, thisIndex = agg.thisIndex + 1} :
                             new {maxIndex = agg.maxIndex, maxValue = agg.maxValue, thisIndex = agg.thisIndex + 1 })).
            maxIndex;
    }

This has the same computational complexity as the other answer, but is more profligate with memory, creating an intermediate answer for each element of the enumerable.