Description

NikolaiVChr

opened on Jun 27, 2024

Issue body actions

I get this:

Traceback (most recent call last):
  File "C:\Users\me\PycharmProjects\f\control1.py", line 17, in <module>
    S = ct.step_info(sysdata=y_out2, T=T2)
  File "C:\Users\me\PycharmProjects\f\venv\lib\site-packages\control\timeresp.py", line 1614, in step_info
    settled = np.where(
IndexError: index -1 is out of bounds for axis 0 with size 0

From this: (just a simple integrator TF)

import control as ct
import numpy as np

num = [0,5]
den = [1,0]

H = ct.TransferFunction(num, den)

t = np.arange(start=0, stop=2, step=1/120)

T2, y_out2 = ct.timeresp.impulse_response(sys=H, T=t)
pyplot.figure(1)
pyplot.plot(T2, y_out2)
pyplot.grid(True)
pyplot.show(block=False)
S = ct.step_info(sysdata=y_out2, T=T2)

pyplot.show()

Control v0.10.0
Numpy 1.26.4
Scipy 1.14.0

Activity

1. NikolaiVChr commented on Jun 27, 2024

   

   NikolaiVChr

   on Jun 27, 2024

   Author

   More actions

   I get same error with:

   num = [1,5]
   den = [1,0]
2. NikolaiVChr commented on Jun 27, 2024

   

   NikolaiVChr

   on Jun 27, 2024

   Author

   More actions

   Oh, and thank you for great library. Its awesome.
3. murrayrm commented on Jun 27, 2024

   

   murrayrm

   on Jun 27, 2024

   Member

   More actions

   The bug is in the step_info function. The impulse response for a pure integrator is a constant output and step_info gets confused when it is passed something that doesn't look like a step response.

   Fixing the bug should be straightforward: we should probably issue a warning when we can't find the features we are looking for in a typical step response.
4. murrayrm

   added

   bug

   on Jun 27, 2024
5. murrayrm

   added this to the 0.10.1 milestone on Jun 27, 2024
6. slivingston commented on Jul 13, 2024

   

   slivingston

   on Jul 13, 2024

   Member

   More actions

   Fixed in #1029
7. slivingston

   closed this as completedon Jul 13, 2024

Issue actions