Standard Clustering
Iteratively repeat until convergence in Lα:
(Step i) for a current value of Γ, Eq. 2 is minimized to wrt. Θ only (that can be done analytically, for example, in the case of classical k-means);
(Step ii) for a current value of Θ, Eq. 2 is minimized to wrt. Γ only (that can also be done analytically).