执行及代码:
/*
*Copyright (c)2014,烟台大学计算机与控制project学院
*All rights reserved.
*文件名:d.cpp
*作 者:张旺华
*完毕日期:2014年11月10日
*版 本 号:v1.0
*
*问题描写叙述:求sin(π/2)和sin(56° )的值精度要求达到小数点后6位;
*输入描写叙述:无
*程序输出:sin(π/2)和sin(56° )的值
*/
#include <iostream>
using namespace std;
double mysin(double);
double myabs(double);
const double pi = 3.1415926;
int main()
{
cout << "sin(π/2)的值为" << mysin(pi / 2) << endl;
cout << "sin(56° )的值为" << mysin(pi * 2 * 56 / 360) << endl;
return 0;
}
double mysin(double x)
{
double sum = x, fact = x, n;
int i = 1, s = 1, m = 1;
do
{
m = m * (i + 1) * (i + 2);
fact=fact*x*x;
n = fact / m;
s = -s;
sum = sum + s * n;
i+=2;
}
while (myabs(n) > 1e-5);
return sum;
}
double myabs(double c)
{
if (c < 0)
c = -c;
else
c = c;
return c;
}
执行结果: