def run_wang04():
    """Run sample problem."""
    x, y = build_sample_ace_problem_wang04(N=200)
    ace_solver = ace.ACESolver()
    ace_solver.specify_data_set(x, y)
    ace_solver.solve()
    try:
        ace.plot_transforms(ace_solver, 'ace_transforms_wang04.png')
        ace.plot_input(ace_solver, 'ace_input_wang04.png')
    except ImportError:
        pass

    return ace_solver