code: def test_cycle_detection_timeseries_numpy(self):
      data = np.random.randn(100)
      cycle_length = cycle_length_est(data)
      assert 1 <= cycle_length <= 100
  
file_path: BigDL/python/chronos/test/bigdl/chronos/data/utils/test_cycle_detection.py
imports: import pytest
  import pandas
  import numpy
  from unittest import TestCase
  from bigdl.chronos.data.utils.cycle_detection import cycle_length_est
  from ...None import op_torch, op_tf2, op_diff_set_all
label_desc: Use image node_id 3 for calling the TestCycleDetectionTimeSeries obj's underlying member method code with example usage: obj.test_cycle_detection_timeseries_numpy() without return types