c++ - 矩阵的相关系数

Question

有人能帮我吗，因为我在这段代码上遇到错误，我不知道哪里出错了。我收到以下信息：错误 C2059：语法错误：'return'，错误 C2334：'{'之前的意外令牌；跳过明显的函数体，错误 C2039: 'rtn' : is not a member of 'corr_coefficient' 请参阅 'corr_coefficient' 的声明 谢谢。

using namespace std;

class corr_coefficient
{
    matrix x, y;
    double sum, C, corr[5];
    int j;  
public:
    double calc_mu(matrix x, int j=0);
    double calc_covariance(matrix x, matrix y, int j); 
    double calc_correlation();
    double StandardDeviation(matrix a, int j=0);
    double return(int i){return corr[i];
    };
    corr_coefficient(matrix x, matrix y);
    };

double corr_coefficient::calc_mu(matrix x, int j)
{
    sum=0;
    for(int i=0; i<C; i++)
    {
        sum = sum+x(i,j);
    }
    return sum/C;
}

double corr_coefficient::calc_covariance(matrix x, matrix y, int j)
{
    double mux=calc_mu(x,0); 
    double muy=calc_mu(y,j); 
    sum=0;
    for (int i=0; i<C; i++)
    {
        sum=sum+(x(i,0)-mux)*(y(i,j)-muy);
    }
    return sum/(C-1); 
}
double corr_coefficient::StandardDeviation(matrix a, int j)

{
    double mua=calc_mu(a,j); 

    sum=0;
    for (int i=0; i<C; i++)
    {
        sum=sum+((a(i,j))-mua)*((a(i,j))-mua);
    }
    return sqrt(sum/(C-1));
}
corr_coefficient::corr_coefficient(matrix x, matrix y)
{
    C=35;
    for (int j=0; j<5; j++)
    {
        corr[j]=calc_covariance(x, y, j)/(StandardDeviation(x, 0)*StandardDeviation(y, j));
    }
}

Answer 1

double return(int i){return corr[i];
};

return是一个关键字。你不能有一个名为return. 只是称它为不同的东西。也许operator[]在这里重载一个合适的运算符？

double operator[](int i){ return corr[i]; }