add lsfPriors

Author: dehann

src/Common.jl

@@ -75,3 +75,30 @@ function sortVarNested(vars::Vector{Symbol})::Vector{Symbol}
 	end
 	return retvars
 end
+
+
+"""
+    $SIGNATURES
+
+Return `::Bool` on whether given factor `fc::Symbol` is a prior in factor graph `dfg`.
+"""
+function isPrior(dfg::G, fc::Symbol)::Bool where G <: AbstractDFG
+  fco = getFactor(dfg, fc)
+  getfnctype(fco) isa FunctorSingleton
+end
+
+"""
+    $SIGNATURES
+
+Return vector of prior factor symbol labels in factor graph `dfg`.
+"""
+function lsfPriors(dfg::G)::Vector{Symbol} where G <: AbstractDFG
+  priors = Symbol[]
+  fcts = lsf(dfg)
+  for fc in fcts
+    if isPrior(dfg, fc)
+      push!(priors, fc)
+    end
+  end
+  return priors
+end

src/DistributedFactorGraphs.jl

@@ -31,6 +31,8 @@ export GenericFunctionNodeData#, FunctionNodeData
 export getSerializationModule, setSerializationModule!
 export pack, unpack
 
+export isPrior, lsfPriors
+
 include("services/AbstractDFG.jl")
 include("services/DFGVariable.jl")