Compute an -net of *Xt* given the distance matrix

[N, eNet] = enet_greedy(D2, e, eNetInit)

*D2*matrix*(n, n)*of canonical squared distance*e*scalar for*eNetInit*vector*(1, N)*of indices of points in the initial -net

*N*scalar for the size of the final -net*eNet*vector*(1, N)*of indices of points in the final -net