JMeterAverageAggregator.cs

using System;
using System.Collections.Generic;
using System.Dynamic;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;
using CsvHelper;

namespace AverageCsv
{
    class Program
    {
        static void Main(string[] args)
        {
            var csvDir = args[0];

            var csvFiles = new DirectoryInfo(csvDir)
                            .GetFiles()
                            .Where(f => f.Extension.EndsWith("csv"))
                            .Where(f => !f.Name.EndsWith("result.csv"));

            var dict = new Dictionary<string, dynamic>();

            var countRegex = new Regex(@"\w\w-(\d+).+");

            foreach (var csvFile in csvFiles)
            {
                Console.WriteLine("Full path: " + csvFile.FullName);

                var threadCount = countRegex.Match(csvFile.Name)
                                            .Groups[1].Value;

                using (var reader = new StreamReader(csvFile.FullName))
                using (var csv = new CsvReader(reader, CultureInfo.InvariantCulture))
                {
                    var records = csv.GetRecords<Record>().ToArray();
                    var recordsFiltered = records;

                    var a = recordsFiltered.Select(x => x.Label + ": " + x.Average).ToArray();
                    Console.WriteLine(string.Join("\n", a));

                    var firstAverage = records.First();

                    foreach (var rec in recordsFiltered)
                    {
                        if (!dict.ContainsKey(rec.Label))
                        {
                            dynamic exp = new ExpandoObject();
                            exp.Label = rec.Label;
                            exp.u10  = 0;
                            exp.u50  = 0;
                            exp.u100 = 0;
                            exp.u150 = 0;
                            exp.u200 = 0;
                            exp.u300 = 0;

                            dict.Add(rec.Label, exp);
                        }

                        var e = dict[rec.Label] as IDictionary<String, Object>;
                        e["u" + threadCount] = rec.Average;
                    }
                }
            }

            using (var writer = new StreamWriter(csvDir + "/result.csv"))
            using (var csv = new CsvWriter(writer, CultureInfo.InvariantCulture))
            {
                var finalRecords = dict.Values.ToList();
                csv.WriteRecords(finalRecords);
            }
        }
    }

    class Record
    {
        public string Label { get; set; }
        public int Average { get; set; }
    }
}