from_graph(graph, points, name=None) [classmethod]

Creates a GeometricGraph from an existing igraph.Graph and point coordinates.

This allows importing externally created graphs into the GeometricGraph framework.

Parameters

• graph (igraph.Graph): An existing igraph Graph object.

• points (numpy.ndarray): Array of point coordinates with shape (n, dim).

• name (str, optional): Name for the graph. If None, uses “Imported Graph”.

Raises

• ValueError: If the number of vertices in the graph doesn’t match the number of points.

Returns

A GeometricGraph object constructed from the existing graph and points.

Example

import igraph as ig
import numpy as np
from proximitygraphs.geometricgraphs import GeometricGraph

# Create an igraph graph
ig_graph = ig.Graph.Famous("Petersen")

# Create corresponding points (circular layout)
n = ig_graph.vcount()
theta = np.linspace(0, 2*np.pi, n, endpoint=False)
points = np.column_stack([np.cos(theta), np.sin(theta)])

# Import into GeometricGraph
geom_graph = GeometricGraph.from_graph(ig_graph, points, name="Petersen Graph")
geom_graph.draw(figsize=(8, 8))