How to use the orbitize.driver.Driver function in orbitize

def test_create_driver_from_table():
    """
    Test creation of Driver object from Table as input
    """
    input_file = os.path.join(orbitize.DATADIR, 'test_val.csv')
    input_table = read_file(input_file)
    myDriver = driver.Driver(input_table, # astropy.table Table of input
                             'MCMC', # name of algorithm for orbit-fitting
                             1, # number of secondary bodies in system
                             1.0, # total system mass [M_sun]
                             50.0, # total parallax of system [mas]
                             mass_err=0.1, # mass error [M_sun]
                             plx_err=0.1) # parallax error [mas]
    _compare_table(myDriver.system.data_table)

def test_create_driver_from_filename():
    """
    Test creation of Driver object from filename as input
    """
    input_file = os.path.join(orbitize.DATADIR, 'test_val.csv')
    myDriver = driver.Driver(input_file, # path to data file
                             'MCMC', # name of algorith for orbit-fitting
                             1, # number of secondary bodies in system
                             1.0, # total system mass [M_sun]
                             50.0, # total parallax of system [mas]
                             mass_err=0.1, # mass error [M_sun]
                             plx_err=0.1) # parallax error [mas]
    _compare_table(myDriver.system.data_table)

def test_run_sampler():

    # initialize sampler
    myDriver = orbitize.driver.Driver(input_file, 'OFTI',
                                      1, 1.22, 56.95, mass_err=0.08, plx_err=0.26)

    s = myDriver.sampler

    # change eccentricity prior
    myDriver.system.sys_priors[1] = priors.LinearPrior(-2.18, 2.01)

    # test num_samples=1
    s.run_sampler(0, num_samples=1)

    # test to make sure outputs are reasonable
    start = time.time()
    orbits = s.run_sampler(1000, num_cores=4)

    end = time.time()
    print()

# expected values from Blunt et al. (2017)
    sma_exp = 48.
    ecc_exp = 0.19
    inc_exp = np.radians(140)

    # test to make sure OFTI values are within 20% of expectations
    assert sma == pytest.approx(sma_exp, abs=0.2*sma_exp)
    assert ecc == pytest.approx(ecc_exp, abs=0.2*ecc_exp)
    assert inc == pytest.approx(inc_exp, abs=0.2*inc_exp)

    # test with only one core
    orbits = s.run_sampler(100, num_cores=1)

    # test with only one epoch
    myDriver = orbitize.driver.Driver(input_file_1epoch, 'OFTI',
                                      1, 1.22, 56.95, mass_err=0.08, plx_err=0.26)
    s = myDriver.sampler
    s.run_sampler(1)
    print()

def test_pt_mcmc_runs(num_threads=1):
    """
    Tests the PTMCMC sampler by making sure it even runs
    """

    # use the test_csv dir
    input_file = os.path.join(orbitize.DATADIR, 'test_val_rv.csv')

    myDriver = Driver(input_file, 'MCMC', 1, 1, 0.01,
                      # mass_err=0.05, plx_err=0.01,
                      system_kwargs={'fit_secondary_mass': True, 'tau_ref_epoch': 0},
                      mcmc_kwargs={'num_temps': 2, 'num_threads': num_threads, 'num_walkers': 100}
                      )

    # run it a little (tests 0 burn-in steps)
    myDriver.sampler.run_sampler(100)

    # run it a little more
    myDriver.sampler.run_sampler(1000, burn_steps=1)

    # run it a little more (tests adding to results object)
    myDriver.sampler.run_sampler(1000, burn_steps=1)

    fixed_index = [index for index, fixed_param in myDriver.sampler.fixed_params]
    clean_params = np.delete(myDriver.sampler.results.post[0], fixed_index)