text: # -*- coding: utf-8 -*-
  # test_ds_optzeros.py
  # This module provides the tests for the ds_freq() function.
  # Copyright 2014 Giuseppe Venturini & Shayne Hodge
  # This file is part of python-deltasigma.
  #
  # python-deltasigma is a 1:1 Python replacement of Richard Schreier's
  # MATLAB delta sigma toolbox (aka "delsigma"), upon which it is heavily based.
  # The delta sigma toolbox is (c) 2009, Richard Schreier.
  #
  # python-deltasigma is distributed in the hope that it will be useful,
  # but WITHOUT ANY WARRANTY; without even the implied warranty of
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  # LICENSE file for the licensing terms.
  
  import unittest
  import numpy as np
  import deltasigma as ds
  import pkg_resources
  import scipy.io
  from os.path import join
  
  
  class TestDSOptZeros(unittest.TestCase):
      """Test function for ds_optzeros()"""
  
      def setUp(self):
          file_path = join('test_data', 'test_ds_optzeros.mat')
          fname = pkg_resources.resource_filename(__name__, file_path)
          self.res = scipy.io.loadmat(fname)['res']
  
      def test_opt_zeros(self):
          """ Test 14 different optzeros() calls. """
          ns = ('n1', 'n2', 'n3', 'n4', 'n5', 'n6', 'n7', 'n8', 'n9', 'n10',
                'n11', 'n12', 'n13', 'n14')
  
          for i, n in enumerate(ns):
              for opt in (0, 1, 2):
                  self.assertTrue(
                      np.allclose(
                          self.res[n][0][0][:, opt], ds.ds_optzeros(i+1, opt),
                          atol=1e-10, rtol=1e-6))
  