Calculate Latency distibutions

LatencyDistribution.cs

void Main()
{
    var random = new Random();
    var data = Enumerable.Range(0, 10000)
        .Select(x => TimeSpan.FromMilliseconds(random.Next(1, 500)))
        .OrderBy(x => x)
        .ToArray();
    Latencies(data).Dump();
}

private static readonly int[] percentiles = new int[] { 10, 25, 50, 75, 90, 95, 99 };

public LatencyDistribution[] Latencies(TimeSpan[] latencies)
{
    var data = new double[percentiles.Length];
    var length = latencies.Length;

    // get percentile latency value
    for (var i = 0; i < percentiles.Length; i++)
    {
        var percentile = percentiles[i];
        var ip = (percentile / 100.0) * length;
        var di = (int)ip;

        // since we're dealing with 0th based ranks we need to
        // check if ordinal is a whole number that lands on the percentile
        // if so adjust accordingly
        if (ip == (double)di)
            di = di - 1;

        if (di < 0)
        {
            di = 0;
        }
        data[i] = latencies[di].TotalMilliseconds;
    }

    var res = new LatencyDistribution[percentiles.Length];
    for (var i = 0; i < percentiles.Length; i++)
    {
        if (data[i] > 0)
        {
            res[i] = new LatencyDistribution
            {
                Percentile = percentiles[i],
                Latency = TimeSpan.FromMilliseconds(data[i]),
            };
        }
    }
    return res;
}

public struct LatencyDistribution
{
    public int Percentile { get; set; }
    public TimeSpan Latency { get; set; }
}