No islands: directed: false vcount: 0 edges: { } One island, no edges: directed: false vcount: 4 edges: { } One island, full graph: directed: false vcount: 4 edges: { 0 1 0 2 0 3 1 2 1 3 2 3 } Two islands, full graphs, no connections between islands: directed: false vcount: 8 edges: { 0 1 0 2 0 3 1 2 1 3 2 3 4 5 4 6 4 7 5 6 5 7 6 7 } Three islands, full graphs, 20 connections between islands. Negative number of islands. Negative island size. Probability out of range. Negative number of edges between islands.