Creates an edge from source vertex to destination vertex. If any given vertex doesn't exist or the edge already exists, a ValueError will be thrown.
(self, source_vertex: T, destination_vertex: T)
| 59 | self.add_edge(edge[0], edge[1]) |
| 60 | |
| 61 | def add_edge(self, source_vertex: T, destination_vertex: T) -> None: |
| 62 | """ |
| 63 | Creates an edge from source vertex to destination vertex. If any |
| 64 | given vertex doesn't exist or the edge already exists, a ValueError |
| 65 | will be thrown. |
| 66 | """ |
| 67 | if not ( |
| 68 | self.contains_vertex(source_vertex) |
| 69 | and self.contains_vertex(destination_vertex) |
| 70 | ): |
| 71 | msg = ( |
| 72 | f"Incorrect input: Either {source_vertex} or " |
| 73 | f"{destination_vertex} does not exist" |
| 74 | ) |
| 75 | raise ValueError(msg) |
| 76 | if self.contains_edge(source_vertex, destination_vertex): |
| 77 | msg = ( |
| 78 | "Incorrect input: The edge already exists between " |
| 79 | f"{source_vertex} and {destination_vertex}" |
| 80 | ) |
| 81 | raise ValueError(msg) |
| 82 | |
| 83 | # Get the indices of the corresponding vertices and set their edge value to 1. |
| 84 | u: int = self.vertex_to_index[source_vertex] |
| 85 | v: int = self.vertex_to_index[destination_vertex] |
| 86 | self.adj_matrix[u][v] = 1 |
| 87 | if not self.directed: |
| 88 | self.adj_matrix[v][u] = 1 |
| 89 | |
| 90 | def remove_edge(self, source_vertex: T, destination_vertex: T) -> None: |
| 91 | """ |