c#使用委托实现辛普森法求多个函数的定积分

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用辛普生法对几个不同的被积函数求指定区间的定积分。被积函数为f(x)，积分区间[a,b]被等分为n=2k份，每份步长为h=(b-a)/n，则积分值为：S≈h((f(a)+f(b))/2 +f(a+h)+…+f(a+(n-1)h))。

运行结果：
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//辛普森法求积分copyright vivi_and_qiao 李伟using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace 辛普森法求积分{    delegate double MyDelegate(double x);    class Function    {        public double f1(double x)        {            return x * x;        }        public string getf1()        {           return "y= x* x";        }        public double f2(double x)        {            return 2 * x + 1;        }        public string getf2()        {            return "y=2 * x + 1";        }        public double f3(double x)        {            return Math.Atan(x);        }        public string getf3()        {            return "y= Math.Atan(x)";        }        public double f4(double x)        {            return Math.Exp(Math.Exp(x));        }        public string getf4()        {            return "y=Math.Exp(Math.Exp(x))";        }    }    class Program    {        public static double jifen(double a,double b,int n ,MyDelegate my)        {            double h = (b - a)/n;            double value=0;            for (int i = 1; i <= n; i++)                value += h * (my(a + (i - 1) * h));            return value;        }        static void Main(string[] args)        {            int n;            double a, b;            Console.WriteLine("请输入精度！");            n = int.Parse(Console.ReadLine());            Console.WriteLine("请输入积分上限");            a = int.Parse(Console.ReadLine());            Console.WriteLine("请输入积分下限！");            b = int.Parse(Console.ReadLine());            Function f=new Function();            MyDelegate my=f.f1;            Console.WriteLine("函数："+f.getf1()+"在积分区间："+"["+a+","+b+"]"+"的积分值为："+jifen(a,b,n,my));            my = f.f2;            Console.WriteLine("函数：" + f.getf2() + "在积分区间：" + "[" + a + "," +b+ "]" + "的积分值为：" + jifen(a, b, n, my));             my = f.f3;            Console.WriteLine("函数：" + f.getf3() + "在积分区间：" + "[" + a + "," +b+ "]" + "的积分值为：" + jifen(a, b, n, my));            my = f.f4;            Console.WriteLine("函数：" + f.getf4() + "在积分区间：" + "[" + a + "," +b+ "]" + "的积分值为：" + jifen(a, b, n, my));            Console.ReadKey();        }    }}

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