"ValueError: When no denominators are given it must be a digital FIR filter" when removing response

[Thomas-Ulrich]

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Bug Summary

I'm looking at old US array data (1995) and I have trouble removing response at (at least) 2 stations.

Code to Reproduce

from obspy.clients.fdsn import Client
from obspy import UTCDateTime

args = {
    "network": "XJ",
    "station": "BLUE",
    "location": "",
    "channel": "BHZ",
    "starttime": UTCDateTime(1995, 11, 22, 4, 22, 35, 9000),
    "endtime": UTCDateTime(1995, 11, 22, 4, 32, 34, 959000),
    "attach_response": True,
}
client = Client("IRIS")
tr = client.get_waveforms(**args)
tr.remove_response(output="ACC")

Error Traceback

Traceback (most recent call last):
  File "/home/ulrich/work/BP/bug_response.py", line 15, in <module>
    tr.remove_response(output="ACC")
  File "/home/ulrich/mambaforge3/lib/python3.10/site-packages/obspy/core/stream.py", line 3237, in remove_response
    tr.remove_response(*args, **kwargs)
  File "/home/ulrich/mambaforge3/lib/python3.10/site-packages/decorator.py", line 232, in fun
    return caller(func, *(extras + args), **kw)
  File "/home/ulrich/mambaforge3/lib/python3.10/site-packages/obspy/core/trace.py", line 282, in _add_processing_info
    result = func(*args, **kwargs)
  File "/home/ulrich/mambaforge3/lib/python3.10/site-packages/obspy/core/trace.py", line 2934, in remove_response
    response.get_evalresp_response(self.stats.delta, nfft,
  File "/home/ulrich/mambaforge3/lib/python3.10/site-packages/obspy/core/inventory/response.py", line 1706, in get_evalresp_response
    response = self.get_evalresp_response_for_frequencies(
  File "/home/ulrich/mambaforge3/lib/python3.10/site-packages/obspy/core/inventory/response.py", line 1651, in get_evalresp_response_for_frequencies
    output, chan = self._call_eval_resp_for_frequencies(
  File "/home/ulrich/mambaforge3/lib/python3.10/site-packages/obspy/core/inventory/response.py", line 1330, in _call_eval_resp_for_frequencies
    raise ValueError(msg)
ValueError: When no denominators are given it must be a digital FIR filter.

ObsPy Version?

1.4.0

Operating System?

Ubuntu

Python Version?

Python 3.10.13

Installation Method?

conda