SuperLU and Mondriaan in .

Creating visual representations {#sec:genvisrep}
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To create visual representations, we employ the method described in [@Fruchterman1991; @Hu2005; @Walshaw2003], generalized to visualizing hypergraphs: we let the vertices of the hypergraph repel each other by an electrostatic-like force and let the hyperedges bind their vertices together like rubber bands. We model this as the minimization of an energy function where we lay out the graph in at least three dimensions (to prevent having to treat the special cases $d = 1$ and $d = 2$ where the form we propose for the energy function is not appropriate). For brevity, we will simply enumerate the vertices of the hypergraph we consider, thus assuming that $V = \{1, \ldots, k\}$ for some $k \in {\mathbf{N}}$.

\[def:graphenergy\] Let $G = (\{1, \ldots, k\}, \{e_1, \ldots, e_l\})$ be a finite weighted hypergraph with vertex weights $w_1, \ldots, w_k > 0$, hyperedge costs $c_1, \ldots, c_l > 0$, and let $d \geq 3$ be the dimension of the target space. Define $$U := \{(x_1, \ldots, x_k) \in {\mathbf{R}}^{d \times k} {\ |\ }\forall 1 \leq i < j \leq k : x_i \neq x_j\}.$$

Then the *energy function of $G$* is defined 