示例#1
0
    def load_results(self, chain_folder, x_dim, run='latest'):
        """Load results from a previous run of ultranest.

        Args:
          chain_folder:
            Path to directory that holds run{i}/ folder(s). These in turn hold
            chain/ and results/ folders, etc.
          x_dim:
            Number of dimensions of posterior.
          run:
            Optional; if 'latest' uses the run{i} folder with highest value
            of i. Else str or int corresponding to the run{i} folder you want
            to access.

        Returns:
          results; which is a list with two dictionaries of results. Note that
          results[1] corresponds to standard ultranest results. See ultranest
          documentation for details.
        """
        number = 0
        res_path = None
        for subdir in glob.glob(chain_folder + '/*'):
            rundir = re.match('.*run(\d+)', subdir, re.IGNORECASE)
            if rundir:
                number_new = int(rundir.group(1))
                if run == 'latest':
                    if number_new > number:
                        number = number_new
                        res_path = subdir
                else:
                    if str(number_new) == str(run):
                        res_path = subdir

        results = un.read_file(res_path, x_dim=x_dim)

        return results
示例#2
0
def test_reactive_run_resume_eggbox(storage_backend):
    from ultranest import ReactiveNestedSampler
    from ultranest import read_file

    def loglike(z):
        chi = (np.cos(z / 2.)).prod(axis=1)
        loglike.ncalls += len(z)
        return (2. + chi)**5
    loglike.ncalls = 0

    def transform(x):
        return x * 10 * np.pi

    paramnames = ['a', 'b']
    ndim = len(paramnames)

    #last_results = None
    folder = tempfile.mkdtemp()
    np.random.seed(1)
    try:
        for i in range(2):
            print()
            print("====== Running Eggbox problem [%d] =====" % (i+1))
            print()
            sampler = ReactiveNestedSampler(paramnames,
                loglike, transform=transform,
                log_dir=folder, resume=True, vectorized=True, draw_multiple=False,
                storage_backend=storage_backend)
            initial_ncalls = int(sampler.ncall)
            num_live_points = 100
            loglike.ncalls = 0
            r = sampler.run(max_iters=200 + i*200,
                max_num_improvement_loops=0,
                min_num_live_points=num_live_points,
                cluster_num_live_points=0)
            sampler.print_results()
            if storage_backend == 'hdf5':
                print("pointstore:", sampler.pointstore.fileobj['points'].shape)
            sampler.pointstore.close()
            print(loglike.ncalls, r['ncall'], initial_ncalls)

            ncalls = loglike.ncalls
            if sampler.mpi_size > 1:
                ncalls = sampler.comm.gather(ncalls, root=0)
                if sampler.mpi_rank == 0:
                    print("ncalls on the different MPI ranks:", ncalls)
                ncalls = sum(sampler.comm.bcast(ncalls, root=0))
            ncalls = ncalls + initial_ncalls
            assert abs(r['ncall'] - ncalls) <= 2 * sampler.mpi_size, (i, r['ncall'], ncalls, r['ncall'] - ncalls)
            assert paramnames == r['paramnames'], 'paramnames should be in results'

        # the results are not exactly the same, because the sampling adds
        #ncalls = loglike.ncalls
        #sampler = ReactiveNestedSampler(paramnames,
        #    loglike, transform=transform,
        #    log_dir=folder, resume=True, vectorized=True, num_test_samples=0)
        #print("pointstore:", sampler.pointstore.fileobj['points'].shape)
        #assert ncalls == loglike.ncalls, (ncalls, loglike.ncalls)
        if storage_backend == 'hdf5':
            sequence, results = read_file(folder, ndim, random=False, num_bootstraps=0)

            print("sampler results: ********************")
            print({k:v for k, v in r.items() if np.asarray(v).size < 20 and k != 'weighted_samples'})
            print("reader results: ********************")
            print({k:v for k, v in results.items() if np.asarray(v).size < 20 and k != 'weighted_samples'})
            for k, v in results.items():
                if k == 'posterior' or k == 'samples':
                    pass
                elif k == 'weighted_samples' or k == 'maximum_likelihood':
                    for k2, v2 in results[k].items():
                        if k2 == 'bootstrapped_weights': continue
                        print("  ", k, "::", k2, np.shape(v2))
                        assert_allclose(r[k][k2], v2)
                elif k.startswith('logzerr') or '_bs' in k or 'Herr' in k:
                    print("   skipping", k, np.shape(v))
                    #assert_allclose(r[k], v, atol=0.5)
                elif k == 'insertion_order_MWW_test':
                    print('insertion_order_MWW_test:', r[k], v)
                    assert r[k] == v, (r[k], v)
                else:
                    print("  ", k, np.shape(v))
                    assert_allclose(r[k], v)

            logw = r['weighted_samples']['logw']
            v = r['weighted_samples']['points']
            L = r['weighted_samples']['logl']

            assert sequence['logz'][-1] - r['logz'] < 0.5, (results['logz'][-1], r['logz'])
            assert sequence['logzerr'][-1] <= r['logzerr_single'], (results['logzerr'][-1], r['logzerr'])
            #assert_allclose(sequence['logz_final'], r['logz_single'], atol=0.3)
            #assert_allclose(sequence['logzerr_final'], r['logzerr_single'], atol=0.1)
            assert r['niter'] <= sequence['niter'] <= r['niter'], (sequence['niter'], r['niter'])
            assert results['niter'] == len(sequence['logz']) == len(sequence['logzerr']) == len(sequence['logvol']) == len(sequence['logwt'])
            assert results['niter'] == len(results['samples'])
            data = np.loadtxt(folder + '/chains/weighted_post.txt', skiprows=1)
            assert_allclose(data[:,0], results['weighted_samples']['weights'])
            assert_allclose(data[:,1], results['weighted_samples']['logl'])
            assert_allclose(v, results['weighted_samples']['points'])
            assert_allclose(logw, results['weighted_samples']['logw'])
            assert_allclose(L, results['weighted_samples']['logl'])

            assert_allclose(L, sequence['logl'])
            #assert_allclose(logw + L, sequence['logwt'])
            assert sequence['logvol'].shape == logw.shape == (len(L),), (sequence['logvol'].shape, logw.shape)
            assert sequence['logwt'].shape == logw.shape == (len(L),), (sequence['logwt'].shape, logw.shape)
            #assert_allclose(logw, sequence['logvols'])
            #assert results['samples_untransformed'].shape == v.shape == (len(L), ndim), (results['samples_untransformed'].shape, v.shape)

    finally:
        shutil.rmtree(folder, ignore_errors=True)