def METHOD_NAME(self):
    ref_job = self.project.create.job.Lammps('ref')
    murn = ref_job.create_job('Murnaghan', 'murn')
    murn.structure = self.basis
    # mock murnaghan run with data from:
    #   ref_job = pr.create.job.Lammps('Lammps')
    #   ref_job.structure = pr.create_structure('Al','fcc', 4.0).repeat(3)
    #   ref_job.potential = '1995--Angelo-J-E--Ni-Al-H--LAMMPS--ipr1'
    #   murn = ref_job.create_job(ham.job_type.Murnaghan, 'murn')
    #   murn.run()
    energies = np.array([-88.23691773, -88.96842984, -89.55374317, -90.00642629,
                         -90.33875009, -90.5618246, -90.68571886, -90.71957679,
                         -90.67170222, -90.54964935, -90.36029582])
    volume = np.array([388.79999999, 397.44, 406.08, 414.71999999,
                       423.35999999, 431.99999999, 440.63999999, 449.27999999,
                       457.92, 466.55999999, 475.19999999])
    murn._hdf5["output/volume"] = volume
    murn._hdf5["output/energy"] = energies
    murn._hdf5["output/equilibrium_volume"] = 448.4033384110422
    murn.status.finished = True
    self.assertIsInstance(murn.plot(plt_show=False), matplotlib.axes.Axes)
    _, ax_list = plt.subplots(ncols=2, nrows=1)
    for i, ax in enumerate(ax_list):
        ax = murn.plot(ax=ax, plot_kwargs={"color": "black", "label": f"plot{i}", "marker": "x"})
        ax.set_title(f"Axis {i+1}")
        self.assertEqual(len(ax.lines), 2)
    with self.subTest(msg="standard polynomial fit"):
        self.assertAlmostEqual(-90.71969974284912, murn.equilibrium_energy)
        self.assertAlmostEqual(448.1341230545222, murn.equilibrium_volume)
    with self.subTest(msg="polynomial fit with fit_order = 2"):
        murn.fit_polynomial(fit_order=2)
        self.assertAlmostEqual(-90.76380033222287, murn.equilibrium_energy)
        self.assertAlmostEqual(449.1529040727273, murn.equilibrium_volume)
    with self.subTest(msg='birchmurnaghan'):
        murn.fit_birch_murnaghan()
        self.assertAlmostEqual(-90.72005405262217, murn.equilibrium_energy)
        self.assertAlmostEqual(448.41909755611437, murn.equilibrium_volume)
    with self.subTest(msg="vinet"):
        murn.fit_vinet()
        self.assertAlmostEqual(-90.72000006839492, murn.equilibrium_energy)
        self.assertAlmostEqual(448.40333840970357, murn.equilibrium_volume)
    with self.subTest(msg='murnaghan'):
        murn.fit_murnaghan()
        self.assertAlmostEqual(-90.72018572197015, murn.equilibrium_energy)
        self.assertAlmostEqual(448.4556825322108, murn.equilibrium_volume)