用c++写一个数据依据方差动态加权的代码
时间: 2023-05-24 12:06:41 浏览: 51
以下是使用 C 语言编写的动态加权方差计算代码:
```
#include <stdio.h>
double update_variance(double current_mean, double current_variance, double new_data, double weight) {
double new_mean = current_mean * (1 - weight) + new_data * weight;
double new_variance = (current_variance * (1 - weight) + weight * (new_data - current_mean) * (new_data - new_mean)) / (1 - weight + weight / weight);
return new_variance;
}
int main() {
double mean = 0;
double variance = 0;
double weight = 0.5; // Dynamic Weight
double data[] = {5.5, 6.1, 5.9, 6.2, 5.8};
int n = sizeof(data) / sizeof(data[0]);
for (int i = 0; i < n; i++) {
variance = update_variance(mean, variance, data[i], weight);
mean = mean * (1 - weight) + data[i] * weight;
printf("Data = %.1f, Mean = %.3f, Variance = %.3f\n", data[i], mean, variance);
}
return 0;
}
```
在这个示例中,我们定义了 `update_variance()` 函数来计算动态加权方差。传入参数包括当前均值、当前方差、新数据和当前权重。函数返回新的方差值。
在 `main()` 函数中,我们传入一些数据并打印每次迭代后的均值和方差。我们还可以手动更改权重,以反映权重对方差估计的影响。
请注意,此代码仅用于示例目的。在实际生产环境中,请使用更健壮的代码并对输入进行适当的验证。