“字段永远不会分配给”警告

Question

我创建了一个抽象类，并且我有一个抽象方法，用于计算用于计算期权价格的随机数向量。以下是我的代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Project1
{
    public abstract class Random_Numbers
    {
        public Random_Numbers()
        {
            newSteps = 0;
            newTrials = 0;
            newStockPrice = 0;
            newSigma = 0;
            newMu = 0;
            newStrike = 0;
            newTenor = 0;
        }

        public Random_Numbers(int Steps, int Trials, double Strike,double StockPrice, double Mu, double Tenor,double Sigma)
        {
            newSteps = Steps;
            newTrials = Trials;
            newStrike = Strike;
            newStockPrice = StockPrice;
            newMu = Mu;
            newTenor = Tenor;
            newSigma = Sigma;
        }
        public int getSteps()
        {
            return newSteps;
        }
        public void setSteps(int Steps)
        {
            newSteps = Steps;
        }
        public double getTrials()
        {
            return newTrials;
        }
        public void setTrials(int Trials)
        {
            newTrials = Trials;
        }
        public double getStockprice()
        {
            return newStockPrice;
        }
        public void setStockprice(double StockPrice)
        {
            newStockPrice = StockPrice;
        }
        public double getSigma()
        {
            return newSigma;
        }
        public void setSigma(double Sigma)
        {
            newSigma = Sigma;
        }
        public double getMu()
        {
            return newMu;
        }
        public void setMu(double Mu)
        {
            newMu = Mu;
        }
        public double getTenor()
        {
            return newTenor;
        }
        public void setTenor(double Tenor)
        {
            newTenor =Tenor;
        }
        public double getStrike()
        {
            return newStrike;
        }
        public void setStrike(double Strike)
        {
            newStrike = Strike;
        }
        public abstract double GenerateRandom();

        public int newSteps;
        public int newTrials;
        public double newStockPrice;
        public double newSigma;
        public double newMu;
        public double newTenor;
        public double newStrike;
    }
}

//My derived class.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Project1
{
    class PriceSimulation:Project1.Random_Numbers
    {
       public override double GenerateRandom()
       {
            double[] r = new double[newSteps + 1];
            double[] p = new double[newSteps + 1];
            double[] v = new double[newSteps + 1];
            double[] d = new double[newSteps + 1];
            double[] l = new double[newSteps + 1];
            double[,] Z = new double[newTrials + 1, newSteps + 1];
            int i = 0;
            int j = 0;
            Random rnd = new Random();
            for (j = 1; j <= newTrials + 1; j++)
            {
                for (i = 1; i <= newSteps + 1; i++)
                {
                    do
                    {
                        r[i] = rnd.Next(-1, 1);
                        p[i] = rnd.Next(-1, 1);
                        v[i] = 2 * r[i] - 1;
                        d[i] = 2 * p[i] - 1;
                        l[i] = Math.Pow(v[i], 2) + Math.Pow(d[i], 2);
                    }
                    while (l[i] >= 1);
                }
                Z[i, j] = Math.Sqrt(-2 * Math.Log(l[i]) / l[i]) * v[i];
            }
            return Z[i, j];
        }

        public double CPriceCalc()
        {
            double[,] Prices = new double[newTrials, newSteps];
            double[,] CPayoff = new double[newTrials, 1];
            double[,] Exercise = new double[newTrials, 1];
            Exercise[newTrials, 1] = newStrike;
            Prices[0, 0] = newStockPrice;
            double dt = newTrials / newSteps;
            int i = 0;
            int j = 0;
            for (j = 1; j <= newTrials; ++j)
            {
                for (i = 1; i <= newSteps; ++i)
                {
                    Prices[i, j] = Prices[i, j - 1] * Math.Exp((newMu - .5 * (Math.Pow(newSigma, 2)) * dt) + newSigma * Math.Sqrt(dt) * Z[i, j]);
                    CPayoff[newTrials, 1] = Math.Max(Prices[newSteps, j] - Exercise[newTrials, 1], 0);

                }
            }
            return CPayoff[newTrials, 1];
        }

        public double PPriceCalc()
        {
            double[,] Prices = new double[newTrials, newSteps];
            double[,] PPayoff = new double[newTrials, 1];
            double[,] Exercise = new double[newTrials, 1];
            Exercise[newTrials, 1] = newStrike;
            Prices[0, 0] = newStockPrice;
            double dt = newTrials / newSteps;
            int i = 0;
            int j = 0;
            for (j = 1; j <= newTrials; ++j)
            {
                for (i = 1; i <= newSteps; ++i)
                {
                    Prices[i, j] = Prices[i, j - 1] * Math.Exp((newMu - .5 * (Math.Pow(newSigma, 2)) * dt) + newSigma * Math.Sqrt(dt) * Z[i, j]);
                    PPayoff[newTrials, 1] = Math.Max(Exercise[newTrials, 1] - Prices[newSteps, j], 0);
                }
            }
            return PPayoff[newTrials, 1];
        }

        public double COptionPrice()
        {
            for (int k = 1; k <= CPayoff.Length; k++)
            {
                Sum += CPayoff[k, 1];
            }
            return CallPrice = (Sum / CPayoff.Length) * Math.Exp(-newMu * newTenor);
        }

        public double POptionPrice()
        {
            double PutPrice;
            for (int k = 1; k <= CPayoff.Length; k++)
            {
                Sum += PPayoff[k, 1];
            }
            return PutPrice = (Sum / PPayoff.Length) * Math.Exp(-newMu * newTenor);
        }

        //Member variables and arrays.
        public double[,] Z;
        public double[,] CPayoff;
        public double[,] PPayoff;
        public double Sum;
        public double CallPrice;
        public double PutPrice;
    }
}

我的问题是我收到警告“Field'Project1.PriceSimulation.Z'永远不会被分配给，并且总是将其默认值设为null”。

Answer 1

我认为你有一个局部变量

double[,] Z = new double[newTrials + 1, newSteps + 1];

遮蔽你的场地

public double[,] Z;