我简单的Java pi计算器似乎总是给无穷大？

Question

我正在为我的Java类编写一个简单的pi计算器，作为我们学习基本循环的一部分，似乎一切正常，除了pi的打印值应为3.14时是无穷大...根据迭代次数。我读到这可能与双变量除以0有关，并且给出了一个奇怪的无穷大输出，而不是普通的Java运行时异常？

这是我的代码：

package lab05;
public class Lab05 {
    public static void main(String[] args) {
        // Variable declarations
        double pie = 3;
        double savepie = 0;
        double term = 0;
        double savei = 0;
        double sign = 1;
        boolean isRangeFound = false;
        int i;
        // For loop
        for (i=0; i <= 1000;) { // Only up to 1000 iterations before loop must end.
            term = (sign * 4) / ((2*i) * (2*i+1) * (2*i+2));
            pie = pie + term;
            sign = (-1 * sign);
            if (isRangeFound==false && (pie >=3.14159265 & pie < 3.14159266)) {
                savepie = pie;
                savei = i;
                isRangeFound = true;
            }
            if (i == 200||i == 500||i == 1000) {
                System.out.print("The value of \u03C0 is: ");
                System.out.printf("%.10f",pie);
                System.out.print(" when i = " + i);
                System.out.println(" ");
            }
            i++;
        }
        // Final output statement
        System.out.println ("The number of iterations to get to 3.14159265 is " + savei + ".");
        System.out.printf("\n\u03C0 = %.10f",savepie);
        System.out.println(" ");
    } 
}

这是我在Netbeans中的输出：

The value of π is: Infinity when i = 200 
The value of π is: Infinity when i = 500 
The value of π is: Infinity when i = 1000 
The number of iterations to get to 3.14159265 is 0.0.

π = 0.0000000000 
BUILD SUCCESSFUL (total time: 0 seconds)

这是我应遵循的指示的链接，其中包含我尝试遵循T的Visual Logic流程图。谢谢。 https://www.dropbox.com/s/2m26a32afedk9yu/Lab05%20Assignment%281%29.pdf?dl=0

Answer 1

当i = 1时，您需要开始循环？您拥有的方式是，当i = 0时，term将是无穷大（由于被零除），所以pie也将是无穷大。