docstr: Checks if the function raises an exception when the user makes an
  inconsistent definition of groups, i.e, only define groups for some
  variables.
docstr_tok: ["Checks","if","the","function","raises","an","exception","when","the","user","makes","an","inconsistent","definition","of","groups",",","i.e",",","only","define","groups","for","some","variables","."]
code: def test_define_problem_with_groups_exception(self):
      """
      Checks if the function raises an exception when the user makes an
      inconsistent definition of groups, i.e, only define groups for some
      variables.
      """
      problem = {
          "num_vars": 8,
          "names": ["x1", "x2", "x3", "x4", "x5", "x6", "x7", "x8"],
          "groups": ["G1", "G1", "G1", "G2", "G2", "G2"],
      }
  
      with raises(ValueError):
          _define_problem_with_groups(problem)
  
imports: from numpy.testing import assert_equal, assert_allclose
  from pytest import raises, fixture, warns, mark
  import numpy
  import warnings
  from SALib.sample.morris.morris import sample, _check_group_membership, _check_if_num_levels_is_even, _compute_optimised_trajectories, _generate_p_star, _compute_b_star, _generate_trajectory, _generate_x_star
  from SALib.util import read_param_file, compute_groups_matrix, _define_problem_with_groups, _compute_delta
label_desc: Use image node_id 8 for calling the TestGroupSampleGeneration obj's underlying member method code with example usage: obj.test_define_problem_with_groups_exception() without return types