### Install PHP Graphviz with Composer

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/getting-started.md

Installs the PHP Graphviz library as a project dependency using Composer.

```shell
composer require alom/graphviz
```

--------------------------------

### Render a Directed Graph with PHP Graphviz

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/getting-started.md

Demonstrates how to create a directed graph using the PHP Graphviz library, including subgraphs and edges, and render it in DOT language.

```php
<?php

require_once __DIR__.'/vendor/autoload.php';

$graph = new Graphviz\Digraph();

$graph
    ->subgraph('cluster_1')
        ->attr('node', ['style' => 'filled', 'fillcolor' => 'blue'])
        ->node('A')
        ->node('B')
    ->end()
    ->edge(array('A', 'B', 'C'))
;

echo $graph->render();

```

--------------------------------

### Convert Graphviz DOT to PNG Image

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/getting-started.md

Shows how to pipe the DOT language output from a PHP script to the Graphviz 'dot' command-line tool to generate a PNG image.

```shell
php test-graphviz.php | dot -Tpng > test-graphviz.png
```

--------------------------------

### Basic Graphviz Digraph Creation

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/examples/basic.md

This snippet demonstrates how to create a directed graph using the Graphviz library. It includes creating subgraphs, setting attributes for nodes and subgraphs, and defining edges. The code utilizes a fluent interface for building the graph structure.

```php
$graph = new Graphviz\Digraph();
$graph
    ->subgraph('cluster_0')
        ->set('style', 'filled')
        ->set('color', 'lightgrey')
        ->attr('node', ['style' => 'filled', 'color' => 'white'])
        ->edge(['a0', 'a1', 'a2', 'a3'])
        ->set('label', 'process #1')
    ->end()
    ->subgraph('cluster_1')
        ->attr('node', ['style' => 'filled'])
        ->edge(['b0', 'b1', 'b2', 'b3'])
        ->set('label', 'process #2')
        ->set('color', 'blue')
    ->end()
    ->edge(['start', 'a0'])
    ->edge(['start', 'b0'])
    ->edge(['a1', 'b3'])
    ->edge(['b2', 'a3'])
    ->edge(['a3', 'a0'])
    ->edge(['a3', 'end'])
    ->edge(['b3', 'end'])
;
```

--------------------------------

### Create Clustered Subgraphs

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/examples/subgraph.md

Demonstrates how to create clustered subgraphs with custom attributes like background color and labels. This involves instantiating a Digraph, defining nodes, and then creating subgraphs using the `subgraph` method.

```php
$graph = new Graphviz\Digraph();
$graph
    ->nodes(['A', 'B', 'C'])
    ->subgraph('cluster_A')
        ->set('bgcolor', '#ffcc00')
        ->set('label', 'Title of the cluster A')
        ->nodes(['D', 'E'])
    ->end()
    ->subgraph('cluster_B')
        ->nodes(['F', 'G'])
    ->end()
    ->edge(['A', 'C'])
    ->edge(['B', 'D', 'F'])
    ->edge(['D', 'E'])
    ->edge(['B', 'G'])
;
```

--------------------------------

### Create Nested Subgraphs

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/examples/subgraph.md

Illustrates the creation of nested subgraphs, where a subgraph can contain other subgraphs. This example shows a chain of nested clusters, each containing a node and an edge.

```php
$graph = new Graphviz\Digraph();
$graph->node('A')->edge(['A', 'B']);

$sub1 = $graph
    ->subgraph('cluster_1')
    ->node('B')
    ->edge(['B', 'C'])
;

$sub2 = $sub1->subgraph('cluster_2')
    ->node('C')
    ->edge(['C', 'D'])
;

$sub3 = $sub2->subgraph('cluster_3')
    ->node('D')
;
```

--------------------------------

### PHP Graphviz Table Node Creation

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/examples/table.md

This snippet shows how to create a Graphviz Digraph and add nodes with HTML-like table labels. It demonstrates the use of `RawText` to ensure that the HTML content within the table is not escaped by Graphviz.

```php
$graph = new Graphviz\Digraph();
$graph
    ->node('escaped', [
        'label' => '<<table><tr><td>Should be escaped</td></tr></table>>',
    ])
    ->node('unescaped', [
        'label' => new Graphviz\RawText('<<table><tr><td>Should not</td><td>be escaped</td></tr></table>>'),
    ])
;
```

--------------------------------

### Access Existing Node

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/nodes.md

Shows how to retrieve an existing `Node` object from the graph using its identifier with the `get()` method and modify its attributes.

```php
$graph = new Graphviz\Digraph();
$graph->node('foo');

$foo = $graph->get('foo');
$foo->attribute('shape', 'record');
```

--------------------------------

### Instantiate Graphviz Graph

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/creation.md

Demonstrates how to create both directed (Digraph) and undirected (Graph) graph objects using the Graphviz library.

```php
$graph = new Graphviz\Digraph();
```

```php
$graph = new Graphviz\Graph();
```

--------------------------------

### Create Node with Attributes

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/nodes.md

Illustrates how to create a node and assign attributes to it by passing an associative array of attributes.

```php
$graph = new Graphviz\Digraph();

$graph->node('foo', [
    'shape' => 'record',
    'label' => 'This is the label of the node'
]);
```

--------------------------------

### Configure and Add Edges to an Undirected Graph

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/creation.md

Illustrates setting graph attributes and adding edges to an undirected graph using the Graphviz\Graph class.

```php
$graph = new Graphviz\Graph();

$graph->set('rankdir', 'LR');
$graph->edge(['Alice', 'Bob', 'Charlie']);
$graph->edge(['Alice', 'Charlie']);
```

--------------------------------

### Configure and Add Edges to a Directed Graph

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/creation.md

Shows how to set graph attributes like 'rankdir' and add edges to a directed graph using the Graphviz\Digraph class.

```php
$graph = new Graphviz\Digraph();

$graph->set('rankdir', 'LR');
$graph->edge(['Alice', 'Bob', 'Charlie']);
$graph->edge(['Alice', 'Charlie']);
```

--------------------------------

### Create Multiple Nodes

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/nodes.md

Shows how to create multiple nodes at once using the `nodes()` method with an array of node identifiers.

```php
$graph = new Graphviz\Digraph();

$graph->nodes(['foo', 'bar', 'baz']);
```

--------------------------------

### Create and Use Subgraphs in Digraph

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/graphviz/subgraph.md

Demonstrates how to create a directed graph and add nodes to different subgraphs. Subgraphs themselves do not provide visual grouping.

```php
$graph = new Graphviz\Digraph();
$graph
    ->nodes(['A', 'B', 'C'])
    ->subgraph('1')
        ->nodes(['D', 'E'])
    ->end()
    ->subgraph('2')
        ->nodes(['F', 'G'])
    ->end()
    ->edge(['A', 'C'])
    ->edge(['B', 'D', 'F'])
    ->edge(['D', 'E'])
    ->edge(['B', 'G'])
;
```

--------------------------------

### Create Graphviz Edge

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/edges.md

Demonstrates the basic creation of an edge between multiple nodes using the `edge` method in PHP. This is the fundamental way to define connections in a graph.

```php
$graph = new Graphviz\Digraph();
$graph->set('rankdir', 'LR');
$graph->edge(['foo', 'bar', 'baz']);
```

--------------------------------

### Create and Use Cluster Subgraphs in Digraph

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/graphviz/subgraph.md

Illustrates creating a directed graph with cluster subgraphs. Subgraphs prefixed with 'cluster_' are rendered with a visual bounding box.

```php
$graph = new Graphviz\Digraph();
$graph
    ->nodes(['A', 'B', 'C'])
    ->subgraph('cluster_A')
        ->nodes(['D', 'E'])
    ->end()
    ->subgraph('cluster_B')
        ->nodes(['F', 'G'])
    ->end()
    ->edge(['A', 'C'])
    ->edge(['B', 'D', 'F'])
    ->edge(['D', 'E'])
    ->edge(['B', 'G'])
;
```

--------------------------------

### Create Multiple Nodes with Attributes

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/nodes.md

Demonstrates creating multiple nodes, some with specific attributes, using an associative array in the `nodes()` method.

```php
$graph = new Graphviz\Digraph();

$graph->nodes([
    'foo',
    'bar' => ['shape' => 'record'],
    'baz',
]);
```

--------------------------------

### Create Single Node

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/nodes.md

Demonstrates how to create a single node in a Graphviz digraph using the `node()` method.

```php
$graph = new Graphviz\Digraph();

$graph->node('foo');
```

--------------------------------

### Style Graphviz Edge with Attributes

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/edges.md

Shows how to apply visual attributes, such as 'style' and 'color', to an edge by passing an associative array as the second argument to the `edge` method. This allows for customization of edge appearance.

```php
$graph = new Graphviz\Digraph();
$graph->edge(['foo', 'bar'], [
    'style' => 'dashed',
    'color' => 'red',
]);
```

--------------------------------

### Render Graph to DOT Format

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/rendering.md

Renders a graph object into the DOT language format. This is the primary method for outputting the graph's structure.

```php
$graph = new Graphviz\Digraph();

$graph->edge(['Alice', 'Bob']);

echo $graph->render();
```

```dot
digraph G {
    Alice -> Bob;
}
```

--------------------------------

### Customize Graph Indentation

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/rendering.md

Allows explicit control over the indentation used in the generated DOT output by specifying a custom indentation string.

```php
$renderer = new Graphviz\Output\DotRenderer('  ');

echo $renderer->render($graph);
```

```dot
digraph G {
  Alice -> Bob;
}
```

--------------------------------

### Set Graph Attribute

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/attributes.md

Demonstrates how to set a global attribute for a directed graph using the 'set' method in PHP. This is useful for defining properties like background color.

```php
# Directed graph
$graph = new Graphviz\Digraph();
$graph->set('bgcolor', 'red');
$graph->nodes(['foo', 'bar']);
```

--------------------------------

### Manipulate Node Object

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/nodes.md

Explains how to obtain a `Node` object using `beginNode()` and then manipulate its attributes using the `attribute()` method.

```php
$graph = new Graphviz\Digraph();
$node = $graph->beginNode('foo');

# Set a value
$node->attribute('shape', 'record');
$node->attribute('label', 'This is the label');

# Get a value
$value = $node->getAttribute('shape');
```

--------------------------------

### Target Graphviz Port Identifier in Edge

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/edges.md

Illustrates how to create an edge that targets a specific port identifier within a node. This is achieved by providing an array containing the node identifier and the port identifier to the `edge` method, enabling more precise connections.

```php
$graph = new Graphviz\Digraph();
$graph->node('week', [
    'shape' => 'record',
    'label' => 'Monday|Tuesday|<wed> Wednesday|Thursday|Friday',
]);

$graph->node('people', [
    'shape' => 'record',
    'label' => 'Alice|<bob> Bob|Charlie',
]);

$graph->edge([
    ['week', 'wed'],
    ['people', 'bob'],
]);
```

--------------------------------

### Set Node, Edge, and Subgraph Attributes

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/attributes.md

Illustrates setting attributes for nodes, edges, and subgraphs within a directed graph using the 'attr' method in PHP. This allows for fine-grained styling of different graph elements.

```php
# Directed graph
$graph = new Graphviz\Digraph();
$graph
    ->attr('node', ['style' => 'filled', 'fillcolor' => 'yellow'])
    ->attr('edge', ['color' => 'blue'])
    ->nodes(['foo', 'bar'])
    ->subgraph('cluster_baz')
        ->attr('graph', ['bgcolor' => 'green'])
        ->nodes(['A', 'B', 'C'])
    ->end()
    ->edge(['foo', 'B'])
    ->edge(['bar', 'C'])
;
```

--------------------------------

### Generate Contributor List

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/contributors.md

This bash command extracts and formats contributor names from Git log history. It reverses the log, formats author names, replaces specific names, and then filters out duplicate entries to provide a unique list of contributors in order of appearance.

```bash
git log --reverse --format="%aN" \
| sed "s/alexandresalome/Alexandre Salomé/g" \
| perl -ne 'if (!defined $x{$_}) { print $_; $x{$_} = 1; }'
```

--------------------------------

### Add Single Line Comment - Graphviz PHP

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/comment.md

Adds a single line comment to a Graphviz graph. Supports custom prefixes and C++ style comments. The commentLine method takes the comment string, an optional boolean to remove leading spaces, and an optional boolean to use C++ style comments.

```php
$graph = new Graphviz\Digraph();
$graph->commentLine('Empty graph');
echo $graph->render();
```

```php
$graph = new Graphviz\Digraph();
$graph->commentLine("Line 1\nLine 2");
echo $graph->render();
```

```php
$graph = new Graphviz\Digraph();
$graph->commentLine('-- ASCII MASTER --//', false);
echo $graph->render();
```

```php
$graph = new Graphviz\Digraph();
$graph->commentLine('C++ style', true, false);
echo $graph->render();
```

--------------------------------

### Add Block Comment - Graphviz PHP

Source: https://github.com/alexandresalome/graphviz/blob/2.1-dev/docs/usage/comment.md

Adds a block comment to a Graphviz graph. Supports multi-line comments and options to disable new lines and spacing. The commentBlock method takes the comment string and an optional boolean to control formatting.

```php
$graph = new Graphviz\Digraph();
$graph->commentBlock('My block comment');
echo $graph->render();
```

```php
$graph = new Graphviz\Digraph();
$graph->commentBlock("My block comment\non multiple lines");
echo $graph->render();
```

```php
$graph = new Graphviz\Digraph();
$graph->commentBlock("** ASCII fan\nNew line\n**", false);
echo $graph->render();
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.