Clean up

Author: YingboMa

test/index_reduction.jl

@@ -35,9 +35,6 @@ edges, vars, vars_asso = sys2bigraph(pendulum)
 
 edges, assign, vars_asso, eqs_asso = ModelingToolkit.pantelides(pendulum)
 
-function new_system(sys, assign, vars_asso, eqs_asso)
-end
-
 @test sort.(edges) == sort.([
  [5, 3],               # 1
  [6, 4],               # 2
@@ -49,9 +46,9 @@ end
  [6, 4, 11, 8],        # 8
  [2, 1, 6, 5, 11, 10], # 9
 ])
-#                  [1, 2, 3, 4, 5,  6,  7,  8,  9, 10,   11]
-#                  [x, y, w, z, x', y', w', z', T, x'', y''] -- how can I get this vector of symbols?
-@test vars_asso == [5, 6, 7, 8, 10, 11, 0,  0,  0,  0,    0]
+#                  [1, 2, 3, 4,   5,   6,  7,  8, 9,   10,   11]
+#                  [x, y, w, z, xˍt, yˍt, w', z', T, xˍt', yˍt']
+@test vars_asso == [5, 6, 7, 8,  10,  11,  0,  0, 0,    0,    0]
 #1: D(x) ~ w
 #2: D(y) ~ z
 #3: D(w) ~ T*x
@@ -75,12 +72,9 @@ idx1_pendulum = [D(x) ~ w,
                  D(z) ~ T*y - g,
                  #0 ~ x^2 + y^2 - L^2,
                  #0 ~ 2x*w + 2y*z,
-                 #D(xˍt) ~ D(w),
-                 D(xˍt) ~ T*x,
                  # D(D(x)) ~ D(w) and substitute the rhs
-                 #D(D(x)) ~ T*x,
+                 D(xˍt) ~ T*x,
                  # D(D(y)) ~ D(z) and substitute the rhs
-                 #D(D(y)) ~ T*y - g,
                  D(yˍt) ~ T*y - g,
                  # 2x*D(D(x)) + 2*D(x)*D(x) + 2y*D(D(y)) + 2*D(y)*D(y) and
                  # substitute the rhs
@@ -90,8 +84,6 @@ first_order_idx1_pendulum = ode_order_lowering(idx1_pendulum)
 
 using OrdinaryDiffEq
 using LinearAlgebra
-#             [x, y, w, z, xˍt, yˍt, T]
-#M = Diagonal([1, 1, 1, 1,   1,   1, 0])
 prob = ODEProblem(ODEFunction(first_order_idx1_pendulum),
         #  [x, y, w, z, xˍt, yˍt, T]
            [1, 0, 0, 0,   0,   0, 0.0],# 0, 0, 0, 0],