void matrixbase_SumRows_ex1()
{
    int rc, ii,jj;
    matrix<double> mat = {
        {-1,  0,  3,  99},
        { 0,  2,  6,   0},
        { 1,  4,  9,   0}
    };
    mat[0][3]=NANUM;
        
    vector vRSum;
    int nRet = mat.SumRows(vRSum);
}
void matrixbase_SumDiagonals_ex1()
{
    int rc, ii,jj;
    matrix<double> mat = {
        {-1,  0,  3,  99},
        { 0,  2,  6,   0},
        { 1,  4,  9,   0}
    };
    mat[0][3]=NANUM;
        
    vector vSum;
    int nEnd = -1;
    int nRet = mat.SumDiagonals(vSum, -2, &nEnd);
}