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Infer.NET development

Compiler-generated variable names

Gate _cases - Used to represent an integer or boolean gate selector via a 1-of-N encoding.
Depth cloning _depthN - Created when a jagged array is used at different indexing depths.
Replication _rep[] - When a variable is used inside a (range) loop, it is replicated for each iteration.
Variable _use & _marginal - The Variable factor is introduced for each variable that needs to be inferred. The output edge of this factor is suffixed by _use. For instance, if we want to infer the variable mean, the input edge to the introduced factor will be called mean, and the output edge will be called mean_use. The marginal distribution is stored in a variable suffixed by _marginal.
Channel 2 _uses[] - When a variable is used multiple times in the model, its uses are disambiguated by adding the _uses[] suffix (one element of this array for each use of the variable). This achieves a 1:1 mapping from variables to edges. An exception to this rule may be made when the same variable is used within gates.
Message _F & _B - Each edge becomes a message. The forward messages are suffixed by _F, and the backward messages are suffixed by _B.
_toDef & _marginal - When the product of the children of replicate has to be stored in a buffer, a variable suffixed by _toDef is used. This allows to optimize the computation of the forward message by dividing the value in the _toDef variable by the backward message. Similarly, if the marginal needs to be buffered, it is stored in a variable suffixed by _marginal. Note that this variable is different from the one introduced by the Variable transform. It differs in that the one here will be called *_F/B_marginal, while the one from Variable will be called *_marginal_F/B. However, they should hold exactly the same value (once both are updated).
Hoisting _hoist - When the value of a variable is computed multiple times inside a loop, but the computations performed are the same for each iteration, then this computation is taken outside the loop. The temporary variable created is called _hoist. If multiple such optimizations need to be made, then the new variables are called _hoist1, …, _hoistN.
Dependency Analysis Sometimes adds special comment statements (called dummy statements in the compiler). These are used to express complex dependencies. For example:

if(priorType) {
    x_F = …
if(!priorType) {
    x_F = ..
// x_F is now defined in all cases <– This is the dummy statement