Issue: Cannot init variables via Vector{Vector{}} indexing.

[bvdmitri]

Discussed in https://github.com/orgs/ReactiveBayes/discussions/490

^{Originally posted by ofSingularMind August 13, 2025}
I had a data variable ω for which I needed to process the components of in separate nodes. I formatted ω as a Vector{Vector{}} and passed it to the model in data = () field. I defined the portion of my model specific to ω as below.

for i in 1:size(ω, 1)
  ω[i][1] ~ UniSGP_AMF_Grad(x[i], v, w, θ, 1) 
  ω[i][2] ~ UniSGP_AMF_Grad(x[i], v, w, θ, 2) 
  ω[i][3] ~ UniSGP_AMF_Grad(x[i], v, w, θ, 3) 
end

Unfortunately, this did not work and lead to node variables not being updated. The solution was to format data object ω as a matrix and to utilize row, column indexing as below.

for i in 1:size(ω, 1)
  ω[i, 1] ~ GenericNode(x[i], v, w, θ, 1) 
  ω[i, 2] ~ GenericNode(x[i], v, w, θ, 2) 
  ω[i, 3] ~ GenericNode(x[i], v, w, θ, 3) 
end

This works fine, but maybe we should allow for Vector{Vector{}} formatting of data variables that need to be split up.

Thanks! Alex