ch1_4.java

来自「Java环境下实现的数值分析程序」· Java 代码 · 共 38 行

class ch1_4{
	static double Sub1(int n){
		double sub=0;
		for(int i=n;i>=2;i--){
			sub=sub+Math.pow((Math.pow(i,2)-1),-1);
		}
		return sub;
	}
	
	static double Sub2(int n){
		double sub=0;
		for(int i=2;i<=n;i++){
			sub=sub+Math.pow((Math.pow(i,2)-1),-1);
		}
		return sub;
	}
	
	static double Sub3(int n){
		double sub=0;
		sub=0.5*(1.5-Math.pow(n,-1)-Math.pow((n+1),-1));
		return sub;
	}
	
	public static void main(String[]args){
		System.out.println("精确值为：");
		System.out.println("Sub1000="+Sub3(1000));
		System.out.println("Sub10000="+Sub3(10000));
		System.out.println("Sub30000="+Sub3(30000));
		System.out.println("按从大到小的顺序计算SN的值：");
		System.out.println("Sub1000="+Sub1(1000));
		System.out.println("Sub10000="+Sub1(10000));
		System.out.println("Sub30000="+Sub1(30000));
	    System.out.println("按从小到大的顺序计算SN的值：");
		System.out.println("Sub1000="+Sub2(1000));
		System.out.println("Sub10000="+Sub2(10000));
		System.out.println("Sub30000="+Sub2(30000));
	}
}