docstr: Test RMS calculation
          
docstr_tok: ["Test","RMS","calculation"]
code: def test_rms(self):
      """Test RMS calculation"""
      # setup
      A = np.random.rand()
      omega = 100
      n_points = 1000
      rms_threshold = 1e-4
      # prep data
      t = np.linspace(0, 2 * np.pi, n_points)
      x = A * np.cos(2 * np.pi * omega * t)
      # test
      x_rms = rms(x)
      golden_rms = A / np.sqrt(2)
      assert (
          np.abs(x_rms - golden_rms) < rms_threshold
      ), f"RMS not matching for A={A}, omega={omega}, n_point={n_points}"
  
imports: import os
  from collections import namedtuple
  from typing import List, Type, Union
  import librosa
  import matplotlib.pyplot
  import numpy
  import pytest
  import scipy
  import soundfile
  import torch
  from nemo.collections.asr.parts.preprocessing.segment import AudioSegment
  from nemo.collections.asr.parts.utils.audio_utils import SOUND_VELOCITY
  from nemo.collections.asr.parts.utils.audio_utils import calculate_sdr_numpy, convmtx_mc_numpy, db2mag, estimated_coherence, generate_approximate_noise_field, get_segment_start, mag2db, pow2db, rms, select_channels, theoretical_coherence, toeplitz
label_desc: Use image node_id 1 for calling the TestAudioUtilsElements obj's underlying member method code with example usage: obj.test_rms() without return types