variance_params(SEMSpec)

Author: Alexey Stukalov

src/frontend/specification/ParameterTable.jl

@@ -388,6 +388,18 @@ function update_se_hessian!(
     return update_partable!(partable, :se, params(fit), se)
 end
 
+function variance_params(partable::ParameterTable)
+    res = [
+        param for (param, rel, from, to) in zip(
+            partable.columns.param,
+            partable.columns.relation,
+            partable.columns.from,
+            partable.columns.to,
+        ) if (rel == :↔) && (from == to)
+    ]
+    unique!(res)
+end
+
 """
     param_values!(out::AbstractVector, partable::ParameterTable,
                   col::Symbol = :estimate)

src/frontend/specification/RAMMatrices.jl

@@ -44,6 +44,17 @@ function latent_vars(ram::RAMMatrices)
     end
 end
 
+function variance_params(ram::RAMMatrices)
+    S_diaginds = Set(diagind(ram.S))
+    varparams = Vector{Symbol}()
+    for (i, param) in enumerate(ram.params)
+        if any(∈(S_diaginds), param_occurences(ram.S, i))
+            push!(varparams, param)
+        end
+    end
+    return unique!(varparams)
+end
+
 ############################################################################################
 ### Constructor
 ############################################################################################