text: import pytest
  
  import numpy as np
  
  from eispac.instr import ccd_offset
  
  
  @pytest.mark.parametrize('wavelength, idl_offset',[
      (185.21, 16.992825),
      ([185.21], 16.992825),
      (np.array([185.21]), 16.992825),
      (np.array([185.21, 195.119, 256.317, 258.375, 284.160]),
       [16.992825, 16.208033,  0.000239, -0.162755, -2.204928])
  ])
  def test_ccd_offset(wavelength, idl_offset):
      offset = ccd_offset(wavelength)
      idl_offset = np.atleast_1d(idl_offset)
      assert np.allclose(offset, idl_offset, atol=1e-5, rtol=0)
  