Qualify parameters in the LowLevelParticleFilters methods for AbstractIdData

`parameters` is not exported by LowLevelParticleFilters, so `forward_trajectory(kf, d::AbstractIdData)` and `smooth(kf, d)` raised `UndefVarError: parameters` when called without the parameter argument.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: baggepinnen

src/subspace.jl

@@ -247,23 +247,23 @@ end
 
 m2vv(x) = collect.(eachcol(x))
 
-function LowLevelParticleFilters.forward_trajectory(kf::LowLevelParticleFilters.AbstractFilter, d::AbstractIdData, p=parameters(kf))
+function LowLevelParticleFilters.forward_trajectory(kf::LowLevelParticleFilters.AbstractFilter, d::AbstractIdData, p=LowLevelParticleFilters.parameters(kf))
     y = time2(output(d))
     u = input(d)
     U = m2vv(u)
     Y = m2vv(y)
     forward_trajectory(kf, U, Y, p)
 end
 
-function LowLevelParticleFilters.smooth(kf::LowLevelParticleFilters.AbstractFilter, d::AbstractIdData, p=parameters(kf))
+function LowLevelParticleFilters.smooth(kf::LowLevelParticleFilters.AbstractFilter, d::AbstractIdData, p=LowLevelParticleFilters.parameters(kf))
     y = time2(output(d))
     u = input(d)
     U = m2vv(u)
     Y = m2vv(y)
     LowLevelParticleFilters.smooth(kf, U, Y, p)
 end
 
-function LowLevelParticleFilters.smooth(kf::LowLevelParticleFilters.AbstractFilter, M::Int, d::AbstractIdData, p=parameters(kf))
+function LowLevelParticleFilters.smooth(kf::LowLevelParticleFilters.AbstractFilter, M::Int, d::AbstractIdData, p=LowLevelParticleFilters.parameters(kf))
     y = time2(output(d))
     u = input(d)
     U = m2vv(u)

test/test_subspace.jl

@@ -166,6 +166,13 @@ end
         @test kf.B == res.B
         @test kf.C == res.C
 
+        sol = ControlSystemIdentification.LowLevelParticleFilters.forward_trajectory(kf, d)
+        @test length(sol.x) == length(d)
+        if pkgversion(ControlSystemIdentification.LowLevelParticleFilters) >= v"3.33.1" # Earlier versions dispatch smooth(::KalmanFilter, ::AbstractIdData) to their own method
+            ssol = ControlSystemIdentification.LowLevelParticleFilters.smooth(kf, d)
+            @test length(ssol.xT) == length(d)
+        end
+
     end
 
     # Test u scaling