private void Solve_Click(object sender, EventArgs e)
        {
            try
            {

                if (double.Parse(this.Angle.Text) < 30
                    || double.Parse(this.Angle.Text) > 80)
                {
                    MessageBox.Show("Podano nieprawidłową wartość kąta pochylenia płaszczyzny kolektora względem poziomu, proszę wprowadzić wartość z podanego zakresu (30-80 stopni)");
                }

            //DAL dal = new DAL();
            //var cities = dal.SelectCities();
            //var CitiesWithParameters = dal.SelectJoinedCityParameters(cities);

            Helper helper = new Helper();

            double Area = double.Parse(this.Area.Text);
            double Consumption = double.Parse(this.Consumption.Text);
            double Angle = double.Parse(this.Angle.Text);
            double Capacity = double.Parse(this.TankCapacity.Text);
            string CityName = this.CityNamesCB.SelectedText;

            double rd = SolveRd(SolveAngleRad(Angle));

            double Psi = SolvePsi(Area, Capacity);
            List<double> Xs = new List<double>();
            List<double> Ys = new List<double>();

            double WWsch;
            double WWsch1;
            double WWsch2;
            double Rb;

            foreach (City city in CitiesWithParameters)
            {
                foreach (var month in Consts.Months)
                {
                    WWsch = Solvewwsh(SolveLongitudeRad(city.Longitude), month.DeltaRad);
                    WWsch1 = Solvewwsh1(SolveLongitudeRad(city.Longitude), month.DeltaRad);
                    WWsch2 = Solvewwsh2(SolveLongitudeRad(city.Longitude), month.Delta, SolveAngleRad(Angle));
                    Rb = SolveRb(helper.GetLowerValue(WWsch1, WWsch2), SolveLongitudeRad(city.Longitude), SolveAngleRad(Angle), month.DeltaRad, WWsch);

                    MonthCoefficients monthCoefficients = new MonthCoefficients(WWsch, WWsch1, WWsch2, Rb);
                    city.monthCoefficientsList.Add(monthCoefficients);
                }
                city.rb_avg = helper.GetAverage(city.monthCoefficientsList.Select(x => x.Rb).ToList());
            }

            foreach (City city in CitiesWithParameters)
            {
                for (int i = 0; i < city.CityParametersList.Count(); i++)
                {
                    Radiation radiation = new Radiation();
                    radiation.IDHkJ = SolveIDHkJ(city.CityParametersList[i].IDH, Consts.Months[i].MonthLength);
                    radiation.ISHkJ = SolveISHkJ(city.CityParametersList[i].ISH, Consts.Months[i].MonthLength);
                    radiation.HBeta = SolveHBeta(radiation.ISHkJ, radiation.IDHkJ, city.rb_avg, rd);

                    city.RadiationList.Add(radiation);
                }
            }

            foreach (City city in CitiesWithParameters)
            {
                for (int i = 0; i < city.CityParametersList.Count(); i++)
                {
                    Results results = new Results();
                    results.HBetaMJ = SolveHBetaMJ(city.RadiationList[i].HBeta, Consts.Months[i].MonthLength);
                    results.X = SolveX(Psi, Area, Consts.FrUL, Consts.Ts, Consts.Tz, city.CityParametersList[i].MDBT, Consts.Cw, Consumption);
                    results.Y = SolveY(Area, Consts.FrTa, results.HBetaMJ, Consumption, Consts.Cw, Consts.Ts, Consts.Tz, Consts.Months[i].MonthLength);
                    results.FObl = SolveFObl(results.X, results.Y);
                    results.F = SolveF(results.FObl);
                    results.Qsl = SolveQsl(results.F, Consumption, Consts.Cw, Consts.Ts, Consts.Tz, Consts.Months[i].MonthLength);
                    results.Qkonw = SolveQkonw(results.F, Consumption, Consts.Cw, Consts.Ts, Consts.Tz, Consts.Months[i].MonthLength);
                    results.Efficiency = SolveEfficiency(results.HBetaMJ, Area, results.Qsl);
                    results.Qzap = SolveQzap(results.Qsl, results.Qkonw);

                    city.ResultsList.Add(results);
                }
            }

            City chosenCity = CitiesWithParameters.Where(x => x.Name == CityNamesCB.Text).FirstOrDefault();

            var finalQsl = FinalQsl(chosenCity.ResultsList.Select(x => x.Qsl).ToList());
            FinalQslLbl.Text = finalQsl.ToString();
            var finalQkonw = FinalQkonw(chosenCity.ResultsList.Select(x => x.Qkonw).ToList());
            FinalQkonwLbl.Text = finalQkonw.ToString();
            var finalQzap = FinalQzap(finalQsl, finalQkonw);
            FinalQzapLbl.Text = finalQzap.ToString();
            FinalFLbl.Text = FinalF(finalQzap, finalQsl).ToString();
            var finalHBetaMJ = FinalHBetaMJ(chosenCity.ResultsList.Select(x => x.HBetaMJ).ToList());
            FinalHBetaMJLbl.Text = finalHBetaMJ.ToString();
            FinalEfficiencyLbl.Text = FinalEfficiency(finalHBetaMJ, finalQsl, Area).ToString();
            FinalProfitLbl.Text = FinalProfit(finalQsl, Area).ToString();

            }
            catch (Exception ex)
            {
                MessageBox.Show("Wprowadzono nieprawidłowe dane: \n" + ex.Message);
            }
        }