# Graph::removeVertex

Removes one or several vertices from a graph

### Use only in the MuPAD Notebook Interface.

This functionality does not run in MATLAB.

## Syntax

```Graph::removeVertex(`G`, `v`)
Graph::removeVertex(`G`, `l`)
```

## Description

`Graph::removeVertex(G, v)` removes vertex `v` from graph `G`.

`Graph::removeVertex(G, [v1, ..., vn])` removes vertices `v1...vn` from graph `G`.

`Graph::removeVertex` deletes one or several vertices from a graph. A warning is printed if the specified vertex is not contained in the graph.

 Note:   If a vertex is connected to other vertices with edges, they will be removed from the graph, too!

`Graph::removeVertex(G, v)` removes the vertex `v` from the graph `G`.

`Graph::removeVertex(G, l)` removes all vertices in list `l` from graph `G`.

## Examples

### Example 1

Removing a vertex from a cyclic graph removes also two edges:

```G1 := Graph::createCircleGraph(5): Graph::printGraphInformation(G1)```
```Vertices: [1, 2, 3, 4, 5] Edges: [[1, 2], [2, 3], [3, 4], [4, 5], [5, 1]] Vertex weights: no vertex weights. Edge descriptions: no edge descriptions. Edge weights: no edge weights. Edge costs: no edge costs. Adjacency list (out): 1 = [2], 2 = [3], 3 = [4], 4 = [5], 5 = [1] Adjacency list (in): 1 = [5], 2 = [1], 3 = [2], 4 = [3], 5 = [4] Graph is directed. ```
`plot(Graph::plotCircleGraph(G1))`

```G2 := Graph::removeVertex(G1, [1]): Graph::printGraphInformation(G2)```
```Vertices: [2, 3, 4, 5] Edges: [[2, 3], [3, 4], [4, 5]] Vertex weights: no vertex weights. Edge descriptions: no edge descriptions. Edge weights: no edge weights. Edge costs: no edge costs. Adjacency list (out): 2 = [3], 3 = [4], 4 = [5], 5 = [] Adjacency list (in): 2 = [], 3 = [2], 4 = [3], 5 = [4] Graph is directed. ```
`plot(Graph::plotCircleGraph(G2))`

If more than one vertex is to be removed they must also be specified in a list:

```vertices := [2, 4]: G3 := Graph::removeVertex(G1, vertices): Graph::printGraphInformation(G3)```
```Vertices: [1, 3, 5] Edges: [[5, 1]] Vertex weights: no vertex weights. Edge descriptions: no edge descriptions. Edge weights: no edge weights. Edge costs: no edge costs. Adjacency list (out): 1 = [], 2 = [], 3 = [], 5 = [1] Adjacency list (in): 1 = [5], 2 = [], 3 = [], 5 = [] Graph is directed. ```
`plot(Graph::plotCircleGraph(G3))`

## Parameters

 `l` A list of vertices `v` A vertex `G` A graph

Graph