我刚刚学习 C++，所以我开始制作一个简单的程序来近似 pi 的值，使用以下系列： Pi ^ 6 / 960 = 1 + 1 / 3 ^ 6 + 1 / 5 ^ 6... 和依此类推，继续使用 6 次方的奇数分母。这是我的代码：
/*-------------------------------------------
* AUTHOR: *
* PROGRAM NAME: Pi Calculator *
* PROGRAM FUNCTION: Uses an iterative *
* process to calculate pi to 16 *
* decimal places *
*------------------------------------------*/
#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;
double pi_approximation = 0; // the approximated value of pi
double iteration = 3; // number used that increases to increase accuracy
double sum = 1; // the cumulative temporary total
int main ()
{
while (true) // endlessly loops
{
sum = sum + pow(iteration,-6); // does the next step in the series
iteration = iteration + 2; // increments iteration
pi_approximation = pow((sum * 960),(1 / 6)); // solves the equation for pi
cout << setprecision (20) << pi_approximation << "\n"; // prints pi to maximum precision permitted with a double
}
}
代码似乎工作正常（变量“总和”和“迭代”都正确增加）到这一行：
pi_approximation = pow((sum * 960),(1 / 6)); // solves the equation for pi
由于某种原因，'pi_approximation' 保留其值 1，因此打印到 'cout' 的文本为“1”。