# Source code for landlab.graph.voronoi.voronoi

```import numpy as np

from ..graph import Graph
from .voronoi_to_graph import VoronoiDelaunayToGraph

[docs]
class DelaunayGraph(Graph):

"""Graph of a voronoi grid.

Examples
--------
>>> from landlab.graph import DelaunayGraph
"""

[docs]
def __init__(
):
"""Create a voronoi grid.

Parameters
----------
nodes : tuple of array_like
Coordinates of every node. First *y*, then *x*.

Examples
--------
>>> from landlab.graph import DelaunayGraph
>>> node_x = [0.0, 1.0, 2.0, 0.9, 1.9, 2.9]
>>> node_y = [0, 0, 0, 2, 2, 2]
>>> graph = DelaunayGraph((node_y, node_x), sort=True)
>>> graph.x_of_node
array([ 0. ,  1. ,  2. ,  0.9,  1.9,  2.9])
>>> graph.y_of_node
array([ 0.,  0.,  0.,  2.,  2.,  2.])
array([[0, 1], [1, 2],
[0, 3], [1, 3], [1, 4], [2, 4], [2, 5],
[3, 4], [4, 5]])
array([[ 0,  2, -1, -1], [ 1,  4,  3,  0], [ 6,  5,  1, -1],
[ 7,  2,  3, -1], [ 8,  7,  4,  5], [ 8,  6, -1, -1]])
array([[3, 2, 0], [5, 4, 1], [7, 3, 4], [8, 5, 6]])

>>> graph.nodes_at_patch
array([[3, 0, 1], [4, 1, 2], [4, 3, 1], [5, 4, 2]])
"""
mesh = VoronoiDelaunayToGraph(
np.vstack((node_y_and_x[1], node_y_and_x[0])).T,