Node tag plugin

GraphPPL provides a built-in plugin to mark factor nodes with a specific tag for later analysis or debugging purposes.

NodeTagPlugin

The plugin allows to specify the tag in the where { ... } block during the node construction. Here how it works:

@model function submodel(y, x, z)
    y ~ Normal(x, z) where { tag = "from submodel" }
end

@model function mainmodel()
    x ~ Normal(0.0, 1.0)
    z ~ Normal(0.0, 1.0)
    y ~ submodel(x = x, z = z)
end

In this example we have created three Normal factor nodes and would like to access the one which has been created within the submodel. To do that, we need to instantiate our model with the GraphPPL.NodeTagPlugin plugin.

model = GraphPPL.create_model(
    GraphPPL.with_plugins(
        mainmodel(),
        GraphPPL.PluginsCollection(GraphPPL.NodeTagPlugin())
    )
)

After, we can fetch all the nodes with a specific tag using the GraphPPL.by_nodetag function.

by_nodetag(tag)

labels = collect(filter(GraphPPL.by_nodetag("from submodel"), model))
foreach(labels) do label
    println(GraphPPL.getname(label))
end

Distributions.Normal