Figure 2:

Graphical representation of the sets Γ and Γ_f. (a) ${\text{Θ}}_{\beta }\subset {ℂ}^N$ is the extension of the set Γ as a function of the parameter β. (b) Extension of Γ_f into the region $\mathcal{F}\subset {ℂ}^{N_{\mathbf{f}}}$.