Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly
Sign up
Appearance settings

Commit 0fc7b9d

Browse files
committed
Generate adjacency matrix for graph.
1 parent dbb7a64 commit 0fc7b9d

File tree

2 files changed

+118
-0
lines changed

2 files changed

+118
-0
lines changed

‎src/data-structures/graph/Graph.js‎

Lines changed: 37 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -158,6 +158,43 @@ export default class Graph {
158158
return this;
159159
}
160160

161+
/**
162+
* @return {object}
163+
*/
164+
getVerticesIndices() {
165+
const verticesIndices = {};
166+
this.getAllVertices().forEach((vertex, index) => {
167+
verticesIndices[vertex.getKey()] = index;
168+
});
169+
170+
return verticesIndices;
171+
}
172+
173+
/**
174+
* @return {*[][]}
175+
*/
176+
getAdjacencyMatrix() {
177+
const vertices = this.getAllVertices();
178+
const verticesIndices = this.getVerticesIndices();
179+
180+
// Init matrix with zeros.
181+
const adjacencyMatrix = Array(vertices.length).fill(null).map(() => {
182+
return Array(vertices.length).fill(0);
183+
});
184+
185+
// Fill the columns.
186+
vertices.forEach((vertex, vertexIndex) => {
187+
vertex.getNeighbors().forEach((neighbor) => {
188+
const neighborIndex = verticesIndices[neighbor.getKey()];
189+
adjacencyMatrix[vertexIndex][neighborIndex] = this.isDirected ?
190+
this.findEdge(vertex, neighbor).weight :
191+
1;
192+
});
193+
});
194+
195+
return adjacencyMatrix;
196+
}
197+
161198
/**
162199
* @return {string}
163200
*/

‎src/data-structures/graph/__test__/Graph.test.js‎

Lines changed: 81 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -300,4 +300,85 @@ describe('Graph', () => {
300300
expect(graph.getNeighbors(vertexD).length).toBe(1);
301301
expect(graph.getNeighbors(vertexD)[0].getKey()).toBe(vertexC.getKey());
302302
});
303+
304+
it('should return vertices indices', () => {
305+
const vertexA = new GraphVertex('A');
306+
const vertexB = new GraphVertex('B');
307+
const vertexC = new GraphVertex('C');
308+
const vertexD = new GraphVertex('D');
309+
310+
const edgeAB = new GraphEdge(vertexA, vertexB);
311+
const edgeBC = new GraphEdge(vertexB, vertexC);
312+
const edgeCD = new GraphEdge(vertexC, vertexD);
313+
const edgeBD = new GraphEdge(vertexB, vertexD);
314+
315+
const graph = new Graph();
316+
graph
317+
.addEdge(edgeAB)
318+
.addEdge(edgeBC)
319+
.addEdge(edgeCD)
320+
.addEdge(edgeBD);
321+
322+
const verticesIndices = graph.getVerticesIndices();
323+
expect(verticesIndices).toEqual({
324+
A: 0,
325+
B: 1,
326+
C: 2,
327+
D: 3,
328+
});
329+
});
330+
331+
it('should generate adjacency matrix for undirected graph', () => {
332+
const vertexA = new GraphVertex('A');
333+
const vertexB = new GraphVertex('B');
334+
const vertexC = new GraphVertex('C');
335+
const vertexD = new GraphVertex('D');
336+
337+
const edgeAB = new GraphEdge(vertexA, vertexB);
338+
const edgeBC = new GraphEdge(vertexB, vertexC);
339+
const edgeCD = new GraphEdge(vertexC, vertexD);
340+
const edgeBD = new GraphEdge(vertexB, vertexD);
341+
342+
const graph = new Graph();
343+
graph
344+
.addEdge(edgeAB)
345+
.addEdge(edgeBC)
346+
.addEdge(edgeCD)
347+
.addEdge(edgeBD);
348+
349+
const adjacencyMatrix = graph.getAdjacencyMatrix();
350+
expect(adjacencyMatrix).toEqual([
351+
[0, 1, 0, 0],
352+
[1, 0, 1, 1],
353+
[0, 1, 0, 1],
354+
[0, 1, 1, 0],
355+
]);
356+
});
357+
358+
it('should generate adjacency matrix for directed graph', () => {
359+
const vertexA = new GraphVertex('A');
360+
const vertexB = new GraphVertex('B');
361+
const vertexC = new GraphVertex('C');
362+
const vertexD = new GraphVertex('D');
363+
364+
const edgeAB = new GraphEdge(vertexA, vertexB, 2);
365+
const edgeBC = new GraphEdge(vertexB, vertexC, 1);
366+
const edgeCD = new GraphEdge(vertexC, vertexD, 5);
367+
const edgeBD = new GraphEdge(vertexB, vertexD, 7);
368+
369+
const graph = new Graph(true);
370+
graph
371+
.addEdge(edgeAB)
372+
.addEdge(edgeBC)
373+
.addEdge(edgeCD)
374+
.addEdge(edgeBD);
375+
376+
const adjacencyMatrix = graph.getAdjacencyMatrix();
377+
expect(adjacencyMatrix).toEqual([
378+
[0, 2, 0, 0],
379+
[0, 0, 1, 7],
380+
[0, 0, 0, 5],
381+
[0, 0, 0, 0],
382+
]);
383+
});
303384
});

0 commit comments

Comments
(0)

AltStyle によって変換されたページ (->オリジナル) /