Closed
Description
Description
I have the following code in a file bug.py
import control as ct
G = ct.tf([1, 1], [1, 0.5, 4])
Wp = ct.tf([2, -2.2, 1], [3, 0.2, 0.01])
k, cl, p, info = ct.mixsyn(G, Wp)and when I run it it seems to hang forever. Compare this to the MATLAB equivalent
G = tf([1, 1], [1, 0.5, 4])
Wp = tf([2, -2.2, 1], [3, 0.2, 0.01])
[K,CL,GAM,info] = mixsyn(G, Wp)which runs fine.
Expand for MATLAB output
G =
s + 1
---------------
s^2 + 0.5 s + 4
Continuous-time transfer function.
Wp =
2 s^2 - 2.2 s + 1
--------------------
3 s^2 + 0.2 s + 0.01
Continuous-time transfer function.
K =
A =
x1 x2 x3 x4
x1 -0.06667 -0.05333 0 0
x2 0.0625 2.233e-31 -5.716e-32 -2.849e-32
x3 205.1 1574 -398.1 -197.9
x4 -2.098e-15 -1.612e-14 2 2.056e-15
B =
u1
x1 2
x2 -9.533e-34
x3 -8.344e-17
x4 6.879e-17
C =
x1 x2 x3 x4
y1 205.1 1574 -397.6 -195.9
D =
u1
y1 0
Continuous-time state-space model.
CL =
A =
x1 x2 x3 x4 x5
x1 -0.06667 -0.05333 -2 -1 0
x2 0.0625 0 0 0 0
x3 0 0 -0.5 -2 205.1
x4 0 0 2 0 0
x5 0 0 -2 -1 -0.06667
x6 0 0 9.533e-34 4.767e-34 0.0625
x7 0 0 8.344e-17 4.172e-17 205.1
x8 0 0 -6.879e-17 -3.439e-17 -2.098e-15
x6 x7 x8
x1 0 0 0
x2 0 0 0
x3 1574 -397.6 -195.9
x4 0 0 0
x5 -0.05333 0 0
x6 2.233e-31 -5.716e-32 -2.849e-32
x7 1574 -398.1 -197.9
x8 -1.612e-14 2 2.056e-15
B =
u1
x1 2
x2 0
x3 0
x4 0
x5 2
x6 -9.533e-34
x7 -8.344e-17
x8 6.879e-17
C =
x1 x2 x3 x4 x5 x6 x7
y1 -0.3889 2.649 -0.6667 -0.3333 0 0 0
x8
y1 0
D =
u1
y1 0.6667
Input groups:
Name Channels
U1 1
Output groups:
Name Channels
Y1 1
Continuous-time state-space model.
GAM =
0.6686
info =
hinfINFO with properties:
gamma: 0.6733
X: [4×4 double]
Y: [4×4 double]
Ku: [205.0868 1.5738e+03 -397.5912 -195.9132]
Kw: [30.4970 234.2721 -58.9574 -29.3820]
Lx: [4×1 double]
Lu: 0
Preg: [3×2 ss]
AS: [2×2 ss]
Hardware & Versions
- Apple MacBook M1 Pro with macOS 13.5 (22G74)
- Python 3.11.7 via Homebrew,
control.__version__is0.9.4andslycot.__version__is0.5.4 - MATLAB R2022b Update 5, 9.13.0.2193358 (maci64) pretty sure it runs on Rosetta
Trace
I tried to run the code with
$ python3 -m trace --trace bug.py
and the code hangs (forever?) at
...
synthesis.py(1306): LW7 = m2*np2 + np2*np2 + m2*m2 + max(nd1*nd1 + max(2*nd1, (nd1 + nd2)*np2),\
synthesis.py(1309): ldwork = LW1 + max(1, LW2, LW3, LW4, LW5 + max(LW6,LW7))
synthesis.py(1310): out = _wrapper.sb10ad(job,n,m,np,ncon,nmeas,gamma,A,B,C,D,gtol,actol,liwork,ldwork)
I'll try to run this again later on an x86 machine, but I suspect this problem is only on M1.