 # How to ignore the directions in dijkstra's algorithm

The code I used to create the graph is as below.

``````CREATE (a:Location {name: 'A'}),
(b:Location {name: 'B'}),
(c:Location {name: 'C'}),
(d:Location {name: 'D'}),
(e:Location {name: 'E'}),
(f:Location {name: 'F'}),
(a)-[:ROAD {cost: 50}]->(b),
(a)-[:ROAD {cost: 50}]->(c),
(a)-[:ROAD {cost: 100}]->(d),
(b)-[:ROAD {cost: 40}]->(d),
(c)-[:ROAD {cost: 40}]->(d),
(c)-[:ROAD {cost: 80}]->(e),
(d)-[:ROAD {cost: 30}]->(e),
(d)-[:ROAD {cost: 80}]->(f),
(e)-[:ROAD {cost: 40}]->(f);
``````

And the graph is as below.

Actually I want to create bidirectional relationships. since it is not possible, I have created like this.
To find the shortest path between "A" node and "F" node using dijkstra's algorithm, I used the following code.

``````CALL gds.graph.create(
'myGraph',
'Location',
'ROAD',
{
relationshipProperties: 'cost'
}
)
``````

``````MATCH (source:Location {name: 'A'}), (target:Location {name: 'F'})
CALL gds.beta.shortestPath.dijkstra.stream('myGraph', {
sourceNode: id(source),
targetNode: id(target),
relationshipWeightProperty: 'cost'
})
YIELD index, sourceNode, targetNode, totalCost, nodeIds, costs
RETURN
index,
gds.util.asNode(sourceNode).name AS sourceNodeName,
gds.util.asNode(targetNode).name AS targetNodeName,
totalCost,
[nodeId IN nodeIds | gds.util.asNode(nodeId).name] AS nodeNames,
costs
ORDER BY index
``````

Output is as below.

This is fine. But when i tried to find the shortest path between "F" to "A" by using same code just by reversing the source and target nodes

``````MATCH (source:Location {name: 'F'}), (target:Location {name: 'A'})
CALL gds.beta.shortestPath.dijkstra.stream('myGraph', {
sourceNode: id(source),
targetNode: id(target),
relationshipWeightProperty: 'cost'
})
YIELD index, sourceNode, targetNode, totalCost, nodeIds, costs
RETURN
index,
gds.util.asNode(sourceNode).name AS sourceNodeName,
gds.util.asNode(targetNode).name AS targetNodeName,
totalCost,
[nodeId IN nodeIds | gds.util.asNode(nodeId).name] AS nodeNames,
costs
ORDER BY index
``````

Output is as below

I think the reason is because there is no directed relation ships from "F" to "A".
I want to ignore the directions of relationships while calculating the dijkstra's shortest path.
Please tell me how can i ignore the directions of relationships in dijkstra's algorithm.
If this is not the reason, please tell me the code to find dijksra's shortest path between "F" to "A".
Thanks in advance.

If you want to reverse the direction of your relationships you'll need to use the `orientation` configuration option when you load your data, not just swap source/target in the algo call:

``````CALL gds.graph.create(
'myGraph',
'Location',
'ROAD',
{
relationshipProperties: 'cost',
orientation:'REVERSE'
}
)
``````

you can also set `orientation:'UNDIRECTED'` to load a graph without directed edges (inmemory, we duplicate the edges).

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