converting std::array<T,N> to std::vector<T>

[muzammil360]

@genbattle, don't you think it would be a better idea if std::vector<T> is used instead of std::array<T,N>. This way one can have a more dynamic design.

I understand std::array is probably a bit faster than std::vector but perhaps not too much.

I have changed std::array<T,N> to std::vector<T> in my code because I needed it post-compilation based on dataset.

Are you aware of any significant speed drops?

[genbattle]

I've already had this discussion in #8. The synopsis is that a std::vector<std::vector<T>> is less efficient because of extra indirection and allocations, and it also means your rows might be of differing lengths, there's nothing to enforce consistent lengths at compile time with vector.

I have been considering creating a N-dimensional array class specifically for this library to solve this problem and provide more runtime flexibility. Another solution would be using a single std::vector<T> instead of std::vector<std::array<T,N>> and defining a separate parameter for stride (row length).

I'll implement an N-dimensional array class when I have time, but I won't be changing the code to use std::vector<std::vector<T>> in the meantime.