SemImply: vars and params API

Author: alyst

src/StructuralEquationModels.jl

@@ -49,6 +49,7 @@ include("observed/EM.jl")
 include("frontend/specification/Sem.jl")
 include("frontend/specification/documentation.jl")
 # imply
+include("imply/abstract.jl")
 include("imply/RAM/symbolic.jl")
 include("imply/RAM/generic.jl")
 include("imply/empty.jl")

src/imply/abstract.jl

@@ -0,0 +1,30 @@
+
+vars(imply::SemImply) = vars(imply.ram_matrices)
+observed_vars(imply::SemImply) = observed_vars(imply.ram_matrices)
+latent_vars(imply::SemImply) = latent_vars(imply.ram_matrices)
+
+nvars(imply::SemImply) = nvars(imply.ram_matrices)
+nobserved_vars(imply::SemImply) = nobserved_vars(imply.ram_matrices)
+nlatent_vars(imply::SemImply) = nlatent_vars(imply.ram_matrices)
+
+params(imply::SemImply) = params(imply.ram_matrices)
+nparams(imply::SemImply) = nparams(imply.ram_matrices)
+
+function check_acyclic(A::AbstractMatrix)
+    # check if the model is acyclic
+    acyclic = isone(det(I-A))
+
+    # check if A is lower or upper triangular
+    if istril(A)
+        @info "A matrix is lower triangular"
+        return LowerTriangular(A)
+    elseif istriu(A)
+        @info "A matrix is upper triangular"
+        return UpperTriangular(A)
+    else
+        if acyclic
+            @info "Your model is acyclic, specifying the A Matrix as either Upper or Lower Triangular can have great performance benefits.\n" maxlog=1
+        end
+        return A
+    end
+end