Contradiction about deterministic factor nodes? #437
Description
Referring to the page: https://docs.rxinfer.ml/stable/manuals/model-specification/
Statement 1:
Note:
The RxInfer.jl package uses the ~ operator for modelling both stochastic and deterministic relationships between random variables. However, GraphPPL.jl also allows to use := operator for deterministic relationships.
Statement 2:
In contrast to other probabilistic programming languages in Julia, RxInfer does not allow use of = operator for creating deterministic relationships between (latent)variables. Instead, we can use := operator for this purpose. For example:
t ~ Normal(mean = 0.0, variance = 1.0)
x := exp(t) # x is linked deterministically to t
y ~ Normal(mean = x, variance = 1.0)
Questions:
What is the best practice when defining deterministic factor nodes? It seems wrong to use = (but I have used code in the past that worked when I used =). Is the best practice to use := or ~ as well? It seems to me that one wants to make it real obvious when we have a deterministic factor node. Why not enforce the use of := ?
Thanks for helping.
Kobus