fix plr for MISO systems

closes #171
baggepinnen · Jan 17, 2025 · a8ebe4c · a8ebe4c
1 parent 6176e6b
commit a8ebe4c
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diff --git a/src/arx.jl b/src/arx.jl
@@ -551,7 +551,7 @@ function plr(d::AbstractIdData, na, nb, nc; initial_order = 20, method = :ls)
     all(nb .<= na) || throw(DomainError(nb, "nb must be <= na"))
     na >= 1 || throw(ArgumentError("na must be positive"))
     # na -= 1
-    y_train, A = getARXregressor(y, u, initial_order, initial_order)
+    y_train, A = getARXregressor(y, u, initial_order, fill(initial_order, d.nu))
     w1 = A \ y_train
     yhat = A * w1
     ehat = yhat - y_train

diff --git a/test/test_arma_plr.jl b/test/test_arma_plr.jl
@@ -35,6 +35,17 @@
     @test freqresptest(G, Gwtls) < sqrt(eps())
     @test freqresptest(G, Gplr) < sqrt(eps())
 
+    ## MISO
+    G = tf(0.8, [1, -0.9], 1)
+    G = [G 2G]
+    u = randn(2,N)
+    y = lsim(G, u, t)[1]
+    e = randn(1,N)
+    yn = y + e
+    na, nb, nc = 1, [1, 1], 1
+    d = iddata(yn, u, 1)
+    Gplr, Gn = ControlSystemIdentification.plr(d, na, nb, nc, initial_order = 10)
+    @test freqresptest(G, Gplr) < 0.11
 end
 
 @testset "arma" begin