graphData

Retrieve graph as digraph object

Since R2022a

Syntax

graph = graphData(planner)

Description

graph = graphData(planner) retrieves graph as a digraph object. The digraph object is created when the plannerPRM object is created with default or user specified values for the MaxNumNodes and MaxConnectionDistance properties.

Examples

Retrieve Graph from Probabilistic Roadmap Path Planner

Load an example map into the workspace, and use it to create an occupancy map with a resolution of 10 cells/meter.

load("exampleMaps.mat","simpleMap");
map = occupancyMap(simpleMap,10);

Create a state space object and update the state space bounds to match the map limits.

ss = stateSpaceSE2;
ss.StateBounds = [map.XWorldLimits; map.YWorldLimits; [-pi pi]];

Create a state validator for the occupancy map using the state space object and set the validation distance.

sv = validatorOccupancyMap(ss,Map=map);
sv.ValidationDistance = 0.01;

Create a probabilistic roadmap path planner object.

planner = plannerPRM(ss,sv);

Retrieve the network graph as a digraph object.

graph = graphData(planner);

Extract the nodes and edges from the graph.

edges = table2array(graph.Edges);
nodes = table2array(graph.Nodes);

Plot the map and graph.

show(sv.Map)
hold on
plot(nodes(:,1),nodes(:,2),"*",Color=[0 0 1],LineWidth=2)
for i = 1:size(edges,1)
    % Samples states at distance 0.02 meters.
    states = interpolate(ss,nodes(edges(i,1),:), ...
                         nodes(edges(i,2),:),0:0.02:1);
    plot(states(:,1),states(:,2),Color=[0 0 1])
end

Input Arguments

planner — Path planner

plannerPRM object

Path planner, specified as a plannerPRM object.

Output Arguments

graph — Graph data

digraph object

Graph data, returned as a digraph object.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2022a