Statically declared 2-D array C++ as data member of a class [duplicate]

Answer 1

I recommend you simply use std::vector<double>(NC*NR).
And index into it by coord.at(i*NC + j) (or coord[i*NC + j], when you code is correct and you want to glean performance out of it).

You'll get contiguous memory and cache friendly loops without doing your own memory allocation. Always prefer RAII when possible.

Answer 2

class Array2D {
public:
    vector<int> v;
    int nc;
    Array2D(int NR, int NC) : v(NR*NC), nc(NC) {}
    int* operator[](int r) { return &v[r*nc]; }
};

int main()
{
    Array2D array2d(2, 3);
    array2d[0][0] = 1;
    array2d[1][2] = 6;
}

This allows you to create a class that will function like a 2D array. It's fast and the data is contiguous.