common.jl: common vars API methods

Author: alyst

src/StructuralEquationModels.jl

@@ -31,6 +31,7 @@ include("additional_functions/commutation_matrix.jl")
 include("frontend/fit/SemFit.jl")
 # specification of models
 include("additional_functions/params_array.jl")
+include("frontend/common.jl")
 include("frontend/specification/checks.jl")
 include("frontend/specification/ParameterTable.jl")
 include("frontend/specification/RAMMatrices.jl")

src/frontend/common.jl

@@ -0,0 +1,48 @@
+# API methods supported by multiple SEM.jl types
+
+"""
+    nparams(semobj)
+
+Return the number of parameters in a SEM model associated with `semboj`.
+
+See also [`params`](@ref).
+"""
+nparams(semobj) = length(params(semobj))
+
+"""
+    nvars(semobj)
+
+Return the number of variables in a SEM model associated with `semobj`.
+
+See also [`vars`](@ref).
+"""
+nvars(semobj) = length(vars(semobj))
+
+"""
+    nobserved_vars(semobj)
+
+Return the number of observed variables in a SEM model associated with `semobj`.
+"""
+nobserved_vars(semobj) = length(observed_vars(semobj))
+
+"""
+    nlatent_vars(semobj)
+
+Return the number of latent variables in a SEM model associated with `semobj`.
+"""
+nlatent_vars(semobj) = length(latent_vars(semobj))
+
+"""
+    param_indices(semobj)
+
+Returns a dict of parameter names and their indices in `semobj`.
+
+# Examples
+```julia
+parind = param_indices(my_fitted_sem)
+parind[:param_name]
+```
+
+See also [`params`](@ref).
+"""
+param_indices(semobj) = Dict(par => i for (i, par) in enumerate(params(semobj)))

src/types.jl

@@ -44,29 +44,6 @@ Return the vector of SEM model parameters.
 """
 params(model::AbstractSem) = model.params
 
-"""
-    nparams(semobj)
-
-Return the number of SEM model parameters.
-"""
-nparams(model::AbstractSem) = length(params(model))
-
-params(model::AbstractSemSingle) = params(model.imply)
-nparams(model::AbstractSemSingle) = nparams(model.imply)
-
-"""
-    param_indices(semobj)
-
-Returns a dict of parameter names and their indices in `semobj`.
-
-# Examples
-```julia
-parind = param_indices(my_fitted_sem)
-parind[:param_name]
-```
-"""
-param_indices(semobj) = Dict(par => i for (i, par) in enumerate(params(semobj)))
-
 """
     SemLoss(args...; loss_weights = nothing, ...)
 
@@ -145,9 +122,6 @@ abstract type SemImply{MS <: MeanStructure, HE <: HessianEvaluation} end
 MeanStructure(::Type{<:SemImply{MS}}) where {MS <: MeanStructure} = MS
 HessianEvaluation(::Type{<:SemImply{MS, HE}}) where {MS, HE <: MeanStructure} = HE
 
-params(imply::SemImply) = params(imply.ram_matrices)
-nparams(imply::SemImply) = nparams(imply.ram_matrices)
-
 "Subtype of SemImply for all objects that can serve as the imply field of a SEM and use some form of symbolic precomputation."
 abstract type SemImplySymbolic{MS, HE} <: SemImply{MS, HE} end
 
@@ -277,7 +251,6 @@ function SemEnsemble(models...; optimizer = SemOptimizerOptim, weights = nothing
 end
 
 params(ensemble::SemEnsemble) = ensemble.params
-nparams(ensemble::SemEnsemble) = length(ensemble.params)
 
 """
     n_models(ensemble::SemEnsemble) -> Integer