Version 2 of benchmark tests for fast rounding code

Round.cs

using System;
using System.Linq;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using System.Runtime.InteropServices;

namespace ClassLibrary2
{
    public class Rounding
    {
        private const int N = 100000;
        private readonly float[] data;
        private readonly float[] data2;
        private readonly int[] output = new int[N];

        public Rounding()
        {
            data = new float[N];
            var random = new Random(42);
            for (var x = 0; x < N; x++)
            {
                data[x] = random.Next(-25, 25) / 10f;
            }
            data2 = new float[N];
            data.CopyTo(data2, 0);
        }

        [Benchmark]
        public int[] Round()
        {
            for (var i = 0; i < N; i++)
            {
                output[i] = (int)Math.Round(data[i], 0, MidpointRounding.AwayFromZero);
            }
            return output;
        }

        [Benchmark]
        public int[] AddAndCast()
        {
            for (var i = 0; i < N; i++)
            {
                output[i] = (int)(data[i] - 0.5f);
            }
            return output;
        }

        [Benchmark]
        public int[] AddAndCast2()
        {
              for (var i = 0; i < N; i++)
            {
                output[i] = data[i] > 0 ? (int)(data[i] + 0.5f) : (int)(data[i] - 0.5f);
            }
            return output;
        }

        [Benchmark]
        public int[] RoundFast()
        {
            for (var i = 0; i < N; i++)
            {
                var num = data[i];
                output[i] = (int)(num + 0.5f * (-1 + 2 * (1 + num - (num + 1) % num) / num));
            }
            return output;
        }


        [Benchmark]
        public int[] ConvertToInt()
        {
            for (var i = 0; i < N; i++)
            {
                output[i] = Convert.ToInt32(data[i]);
            }
            return output;
        }

        [Benchmark]
        public void Native() {
            roundAll(data2.Length, data2);
        }

        [DllImport("nativeFunctions.dll")] // or however you call your dll
        static extern void roundAll(int len, float[] data);
    }

    public class Class1
    {
        public static void Main(string[] args)
        {
            var summary = BenchmarkRunner.Run<Rounding>();
        }
    }
}