Substituting in StateSpace

[freemin7]

I am trying so substitute a variable inside a StateSpace{Continous,Num}.

julia>  Σᵤ
StateSpace{Continuous, Num}
A =
  0       1       0
  0  1 + k₁  1 + k₂
 kᵢ  1 + k₃      k₄
B =
 0
 1
 0
C =
 kᵢ  1 + k₁ + k₃  k₂ + k₄
D =
 1


julia>  substitute(Σᵤ, Dict( kᵢ=> -3))
StateSpace{Continuous, Num}
A =
  0       1       0
  0  1 + k₁  1 + k₂
 kᵢ  1 + k₃      k₄
B =
 0
 1
 0
C =
 kᵢ  1 + k₁ + k₃  k₂ + k₄
D =
 1

Continuous-time state-space model

but the system is unchanged. Is there a better way to go about this?

[baggepinnen]

You'd have to operate on the matrix entries individually, we have no support for this right now.