Reorder simplified exprs

Author: YingboMa

test/direct.jl

@@ -13,9 +13,11 @@ eqs = [σ*(y-x),
        x*y - β*z]
 
 
-simpexpr = Expr[:($(*)(σ, $(+)($(*)(-1, x), y))),
-                :($(+)($(*)(x, $(+)($(*)(-1, z), ρ)), $(*)(-1, y))),
-                :($(+)($(*)(x, y), $(*)(-1, z, β)))]
+simpexpr = [
+ :($(*)(σ, $(+)(y, $(*)(-1, x))))
+ :($(+)($(*)(x, $(+)(ρ, $(*)(-1, z))), $(*)(-1, y)))
+ :($(+)($(*)(x, y), $(*)(-1, z, β)))
+]
 
 for i in 1:3
    @test ModelingToolkit.toexpr.(eqs)[i] == simpexpr[i]