Random selection from list

[tulach]

I need to select Node from NodeList, but based on random. All nodes should have equall probability of beeing selected.

Does anybody know if this is possible?

I made a workaround with assigning each node a number from 1 to N and then first generate the random number and then search for appropriate Node using SearchStep, but this requires for setting numbers for each node manually and I have a lot of nodes in my model.

Is there a way to use a rank of node in the node list?

Thanks for help.

Petr

[dsturrock]

The easiest way is to select it when you actually use it. On the TransferNode use a Selection Goal of Random. Or in a Process use the Route step.

You could also list your nodes in a table instead of a list and randomly select the row of that table.

[tulach]

Thanks for immediate reply David, I just find the route step option myself, but it is good to know that there is no other elegant option.

But as I want to transfer some entity to the node from node list not using a path, I use this construction.

Route -> Assign (NodeState:=Model.Entity.DestinationNode) -> Transfer (to node: NodeState)

I would be nice if we can just pick a random node form list with something like this

List.MyListName.random

Something we can do with populations.

[dsturrock]

Here is a note from one of our developers:

 

I think if you used a Search step like this:

Collection Type: NodeList

Node List Name: The name of the node list to be searched

Search Type: MaximizeExpression

Search Expression: Random.Uniform(0,1)

Then that search will essentially select a node 'randomly' from the searched list. Then store the node found by the Search step into a state variable.

That is basically what the Route step with 'Random' Selection Goal does.

[tulach]

That is more elegant way to do.

Thanks