Beispiel #1
0
    structure = np.zeros((3,3))
    structure[1,2] = 1
    g.add_grid_edges(nodeids, structure=structure, weights=weights, symmetric=False)
    
    # Edges pointing up
    structure = np.zeros((3,3))
    structure[0,1] = 1
    g.add_grid_edges(nodeids, structure=structure, weights=weights+100, symmetric=False)
    
    # Edges pointing down
    structure = np.zeros((3,3))
    structure[2,1] = 1
    g.add_grid_edges(nodeids, structure=structure, weights=weights+200, symmetric=False)
    
    # Source node connected to leftmost non-terminal nodes.
    left = nodeids[:, 0]
    g.add_grid_tedges(left, np.inf, 0)
    # Sink node connected to rightmost non-terminal nodes.
    right = nodeids[:, -1]
    g.add_grid_tedges(right, 0, np.inf)
    
    return nodeids, g

if __name__ == '__main__':
    nodeids, g = create_graph()
    
    plot_graph_2d(g, nodeids.shape)
    
    g.maxflow()
    print(g.get_grid_segments(nodeids))
Beispiel #2
0
import numpy as np
import maxflow

from examples_utils import plot_graph_2d

# Standard 4-connected grid
g = maxflow.Graph[int]()
nodeids = g.add_grid_nodes((5, 5))
g.add_grid_edges(nodeids, 1)
# Equivalent to
# structure = maxflow.vonNeumann_structure(ndim=2, directed=False)
# g.add_grid_edges(nodeids, 1,
#                  structure=structure,
#                  symmetric=False)
plot_graph_2d(g, nodeids.shape, plot_terminals=False)

# 8-connected grid, ignore two nodes
g = maxflow.Graph[int]()
nodeids = g.add_grid_nodes((5, 5))
structure = np.array([[0, 0, 0], [0, 0, 1], [1, 1, 1]])
# Also structure = maxflow.moore_structure(ndim=2, directed=True)
# Nodeid -1 is ignored when adding edges
nodeids[1, 1] = -1
nodeids[3, 2] = -1
g.add_grid_edges(nodeids, 1, structure=structure, symmetric=True)
plot_graph_2d(g, nodeids.shape, plot_terminals=False)

# 24-connected 5x5 neighborhood
g = maxflow.Graph[int]()
nodeids = g.add_grid_nodes((5, 5))
Beispiel #3
0
    structure[1, 2] = 1
    g.add_grid_edges(nodeids, structure=structure, weights=weights, symmetric=False)

    # Edges pointing up
    structure = np.zeros((3, 3))
    structure[0, 1] = 1
    g.add_grid_edges(nodeids, structure=structure, weights=weights+100, symmetric=False)

    # Edges pointing down
    structure = np.zeros((3, 3))
    structure[2, 1] = 1
    g.add_grid_edges(nodeids, structure=structure, weights=weights+200, symmetric=False)

    # Source node connected to leftmost non-terminal nodes.
    left = nodeids[:, 0]
    g.add_grid_tedges(left, np.inf, 0)
    # Sink node connected to rightmost non-terminal nodes.
    right = nodeids[:, -1]
    g.add_grid_tedges(right, 0, np.inf)

    return nodeids, g


if __name__ == '__main__':
    nodeids, g = create_graph()

    plot_graph_2d(g, nodeids.shape)

    g.maxflow()
    print(g.get_grid_segments(nodeids))