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Bug Summary

I'm not quite sure if it's a bug or feature. Remove_response cannot recognize the correct scale for a unit with a metric prefix (such as nm/s). The description on the remove_response webpage says: "VEL velocity, output unit is meters/second" but in reality, it remains in the original prefixed unit.

I can see that in Response._call_eval_resp_for_frequencies it is already prepared to scale a response according to the input unit:

# Scale factor with the same logic as evalresp.
if key in ["CM/S**2", "CM/S", "CM/SEC", "CM"]:
scale_factor[0] = 1.0E2
elif key in ["MM/S**2", "MM/S", "MM/SEC", "MM"]:
scale_factor[0] = 1.0E3
elif key in ["NM/S**2", "NM/S", "NM/SEC", "NM"]:
scale_factor[0] = 1.0E9

but is not used finally:
# XXX: Check if this is really not needed.
# output *= scale_factor[0]

Code to Reproduce

No response

Error Traceback

No response

ObsPy Version?

1.4.0

Operating System?

Windows

Python Version?

3.10.8

Installation Method?

conda