数值分析上机作业代码数分析上机作业代码.docVIP

以下代码纯属自创，都在本人电脑上可以运行,运行软件为eclipse64位 牛顿法： package Newton; import java.text.DecimalFormat; public class Newton { static float a=(float) Math.PI/4; static float b; public static void main(String args[]){ b=(float) (a-((Math.exp(a)-4*Math.cos(a))/(Math.exp(a)+4*Math.sin(a)))); while((a-b)=0.005||(b-a)=0.005){ a=b; b=(float) (a-((Math.exp(a)-4*Math.cos(a))/(Math.exp(a)+4*Math.sin(a)))); System.out.println(b); } DecimalFormat fmt =new DecimalFormat(0.###); System.out.print(the exact value is + fmt.format(b)); } } 迭代： package Diedai; import java.text.DecimalFormat; public class Diedai { static float a = (float) 0.5; static float b; public static void main(String args[]) { b = (float) (a + 2 * Math.cos(a) / Math.exp(a) - 1); while ((a - b) = 0.005 || (b - a) = 0.005) { a = b; b = (float) (a + 2 * Math.cos(a) / Math.exp(a) - 1); } DecimalFormat fmt = new DecimalFormat(0.##); System.out.print(the exact value is + fmt.format(b)); } } 二分法：求x^3-2x^2-4x-7=0,精确到小数点后3位 package Erfenfa; public class Erfenfa { static float i=0; static float a=3; static float b=4; static float c; static float d; static float e; static float f; public static void main(String args[]){ for(i=0;i3;i++){ c=(a+b)/2; if(i==2){ System.out.println(the final number is： +c); break; } d=a*a*a-2*a*a-4*a-7; e=b*b*b-2*b*b-4*b-7; f=c*c*c-2*c*c-4*c-7; if(d*f=0) { b=c; } else{ a=c; } } } } 高斯：解方程组4a+2b+5c=4 -2b+0.5c=-1 -0.875c=5.25 package gaosi; import java.text.DecimalFormat; public class gaosi { public static void main(String args[]) { float a[][] = new float[3][3]; a[0][0] = 4; a[0][1] = 2; a[0][2] = 5; a[1][0] = 0; a[1][1] = -2; a[1][2] = (float) 0.5; a[2][0] = 0; a[2][1]