equationtest.java

数值分析算法源码(java) 这个学期一边学习java一边学习数值分析,因此用java写了一个数值分析算法的软件包numericalAnalysis. [说明] 适合使用者:会java的

package numericalAnalysis.equation;

import java.util.Scanner;
import numericalAnalysis.function.Function;

public class EquationTest {// -------------注意!!!!!!方程f(x)=0的f(x)在下面Function接口写入-----------------------------------------
	public static void main(String[] args) {
		Scanner input = new Scanner(System.in);
		Equation equation;
		MyFunction function;// f(x)=0的f(x)
		String anotherChoice;// 新的求解方法

		System.out.println("\n----------------------------本程序求解方程"
				+ "----------------------------\n\n");
		//确认f(x)已经写入Function接口
		System.out.println("你要的方程f(x)=0的f(x)若未在源码中写好则请先写好,若写好了请按c:\n");
		anotherChoice=input.next();
		function=new MyFunction();
		equation=new Equation(function);//新建这个方程
		
		do {
			int choice = 0;
			boolean retry = true;
			while (retry) {
				retry = false;
				System.out.println();
				System.out.println("1---双点弦截法求得方程的根");
				System.out.println("2---双点弦截法");
				System.out.println("请选择:");
				try {
					choice = Integer.parseInt(input.next());
				} catch (NumberFormatException e) {
					System.out.println("请别胡乱输入!\n");
					retry = true;
				}
			}

			switch (choice) {
			case 1:
				System.out.println("用双点弦截法解方程,方程f(x)=0必须满足:\n" +
						"1.f(a)*f(b)<0\n" +
						"2.f'(x)不等于0,当x属于[a,b]时.");
				//输入a,b
				System.out.println("请输入a:\n");
				double leftEndpoint = input.nextDouble();
				System.out.println("请输入b:\n");
				double rightEndpoint = input.nextDouble();

				System.out.println();
				System.out.println("方程的根:");
				System.out.println(equation.getSolution(leftEndpoint, rightEndpoint));
				break;
			case 2:
				System.out.println("用双点弦截法解方程,方程f(x)=0必须满足:\n" +
						"1.f(a)*f(b)<0\n" +
						"2.f'(x)不等于0,当x属于[a,b]时.");
				//输入a,b
				System.out.println("请输入a:\n");
				leftEndpoint = input.nextDouble();
				System.out.println("请输入b:\n");
				rightEndpoint = input.nextDouble();

				System.out.println();
				System.out.println("计算过程:");
				System.out.println(equation.doubleChordSection(leftEndpoint, rightEndpoint));
				break;
			}

			System.out.println("    要再使用其他方法吗?   y/n:");
			anotherChoice = input.next();
		} while (anotherChoice.equalsIgnoreCase("y"));
	}

	private static class MyFunction implements Function {
		// -------------注意!!!!!!方程f(x)=0的f(x)在此写入-----------------------------------------
		public double f(double x) {
			return Math.pow(x, 3)-Math.pow(x, 2)-x-1;
		}

		public double f(double x, double y) {
			return 0;
		}

	}
}