docs: public Graph<K, VV, EV> filterOnVertices(FilterFunction<Vertex<K, VV>> vertexFilter) {
  
  		DataSet<Vertex<K, VV>> filteredVertices = this.vertices.filter(vertexFilter);
  
  		DataSet<Edge<K, EV>> remainingEdges = this.edges.join(filteredVertices)
  				.where(0).equalTo(0).with(new ProjectEdge<>())
  				.join(filteredVertices).where(1).equalTo(0)
  				.with(new ProjectEdge<>()).name("Filter on vertices");
  
  		return new Graph<>(filteredVertices, remainingEdges, this.context);
  	}