tessl/pypi-pydot
Python interface to Graphviz's Dot language for creating, reading, editing, and visualizing graphs
—
Pending
graph-management.mddocs/
Graph Creation and Management
Core graph objects and operations that form the foundation for building and manipulating graph structures in pydot. These classes provide a Python interface to Graphviz's graph model.
Capabilities
Graph Container (Dot Class)
The primary container for representing complete graphs. Supports directed graphs (digraph), undirected graphs (graph), and strict mode for eliminating duplicate edges.
class Dot:
def __init__(self, graph_name='G', obj_dict=None, graph_type='digraph',
strict=False, suppress_disconnected=False, simplify=False, **attrs):
"""
Create a new graph container.
Parameters:
- graph_name (str): Name of the graph
- obj_dict (dict): Object dictionary for internal use
- graph_type (str): 'digraph' for directed, 'graph' for undirected
- strict (bool): Eliminate multiple edges between same nodes
- suppress_disconnected (bool): Hide disconnected nodes in output
- simplify (bool): Remove redundant elements
- **attrs: Additional graph attributes
"""
def add_node(self, node):
"""Add a node to the graph."""
def add_edge(self, edge):
"""Add an edge to the graph."""
def add_subgraph(self, subgraph):
"""Add a subgraph to the graph."""
def get_node(self, name):
"""
Get node by name.
Returns:
list: List of matching nodes (usually one element)
"""
def get_edge(self, src_or_list, dst=None):
"""
Get edge by source and destination nodes.
Parameters:
- src_or_list: Source node or list/tuple of (src, dst)
- dst: Destination node (if src_or_list is not a list/tuple)
Returns:
list: List of matching edges
"""
def get_nodes(self):
"""Get all nodes in the graph."""
def get_edges(self):
"""Get all edges in the graph."""
def get_subgraphs(self):
"""Get all subgraphs in the graph."""
def del_node(self, name, index=None):
"""
Delete node by name.
Parameters:
- name (str|Node): Node name or Node object
- index (int, optional): Specific index if multiple nodes with same name
Returns:
bool: True if node was deleted
"""
def del_edge(self, src_or_list, dst=None, index=None):
"""
Delete edge by source and destination.
Parameters:
- src_or_list: Source node or list/tuple of (src, dst)
- dst: Destination node (if src_or_list is not a list/tuple)
- index (int, optional): Specific index if multiple edges exist
Returns:
bool: True if edge was deleted
"""
def to_string(self):
"""
Generate raw DOT string representation.
Returns:
str: DOT language representation of the graph
"""
def get_graph_type(self):
"""Get the graph's type ('digraph' or 'graph')."""
def set_graph_defaults(self, **attrs):
"""Set default graph attributes."""
def get_graph_defaults(self):
"""Get default graph attributes."""
def set_node_defaults(self, **attrs):
"""Set default node attributes."""
def get_node_defaults(self):
"""Get default node attributes."""
def set_edge_defaults(self, **attrs):
"""Set default edge attributes."""
def get_edge_defaults(self):
"""Get default edge attributes."""Node Creation and Management
Individual graph vertices with customizable visual and semantic attributes.
class Node:
def __init__(self, name='', obj_dict=None, **attrs):
"""
Create a new node.
Parameters:
- name (str): Unique identifier for the node
- obj_dict (dict): Object dictionary for internal use
- **attrs: Node attributes (shape, color, label, etc.)
"""
def get_name(self):
"""Get the node's name."""
def set_name(self, name):
"""Set the node's name."""
def to_string(self):
"""Generate DOT string representation of the node."""Edge Creation and Management
Connections between nodes with directional and styling properties.
class Edge:
def __init__(self, src='', dst='', obj_dict=None, **attrs):
"""
Create a new edge.
Parameters:
- src (str|Node|list|tuple): Source node identifier, Node object, or
sequence of edge definitions for multiple edges
- dst (str|Node): Destination node identifier or Node object
- obj_dict (dict): Object dictionary for internal use
- **attrs: Edge attributes (color, style, label, etc.)
"""
def get_source(self):
"""Get the source node."""
def get_destination(self):
"""Get the destination node."""
def set_source(self, src):
"""Set the source node."""
def set_destination(self, dst):
"""Set the destination node."""
def to_string(self):
"""Generate DOT string representation of the edge."""Base Graph Class
Foundation class providing common functionality for all graph-like objects.
class Graph:
def __init__(self, graph_name='G', obj_dict=None, graph_type='digraph',
strict=False, suppress_disconnected=False, simplify=False, **attrs):
"""Base graph class - use Dot class instead for main graphs."""Dynamic Attribute Methods
All graph objects support dynamically generated getter/setter methods for Graphviz attributes:
For Dot/Graph objects - 73 attributes including:
get_bgcolor()/set_bgcolor(value)- Background colorget_rankdir()/set_rankdir(value)- Layout direction ('TB', 'LR', etc.)get_fontsize()/set_fontsize(value)- Default font sizeget_label()/set_label(value)- Graph title/label
For Node objects - 38 attributes including:
get_shape()/set_shape(value)- Node shape ('box', 'circle', 'ellipse', etc.)get_color()/set_color(value)- Node border colorget_fillcolor()/set_fillcolor(value)- Node fill colorget_label()/set_label(value)- Node display text
For Edge objects - 61 attributes including:
get_color()/set_color(value)- Edge colorget_arrowhead()/set_arrowhead(value)- Arrow style ('normal', 'dot', 'diamond', etc.)get_style()/set_style(value)- Line style ('solid', 'dashed', 'dotted', etc.)get_label()/set_label(value)- Edge label text
Usage Examples
Creating a Simple Graph
import pydot
# Create directed graph
graph = pydot.Dot("example", graph_type="digraph")
# Add nodes with attributes
start = pydot.Node("start", shape="ellipse", style="filled", fillcolor="lightgreen")
process = pydot.Node("process", shape="box", label="Process Data")
end = pydot.Node("end", shape="ellipse", style="filled", fillcolor="lightcoral")
graph.add_node(start)
graph.add_node(process)
graph.add_node(end)
# Add edges
graph.add_edge(pydot.Edge("start", "process", label="input"))
graph.add_edge(pydot.Edge("process", "end", label="output"))
# Set graph properties
graph.set_rankdir("LR") # Left to right layout
graph.set_bgcolor("white")Working with Node and Edge Collections
# Find nodes by name
nodes = graph.get_node("process")
if nodes:
process_node = nodes[0]
process_node.set_color("blue")
# Iterate through all nodes
for node in graph.get_nodes():
print(f"Node: {node.get_name()}")
# Iterate through all edges
for edge in graph.get_edges():
print(f"Edge: {edge.get_source()} -> {edge.get_destination()}")Install with Tessl CLI
npx tessl i tessl/pypi-pydot