Esempio n. 1
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 def check_cb_op_perm(cb_op, perm):
     mi_cb = cb_op.apply(ra.miller_indices)
     miis = flex.random_permutation(size=ra.miller_indices.size())[:2]
     k = cb_op.apply(ra.miller_indices.select(miis))
     matches = miller.match_indices(k, ra.miller_indices)
     pairs = matches.pairs()
     assert pairs.column(0).all_eq(flex.size_t_range(k.size()))
     miis_cb = pairs.column(1)
     assert perm.select(miis).all_eq(miis_cb)
Esempio n. 2
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 def check_cb_op_perm(cb_op, perm):
   mi_cb = cb_op.apply(ra.miller_indices)
   miis = flex.random_permutation(size=ra.miller_indices.size())[:2]
   k = cb_op.apply(ra.miller_indices.select(miis))
   matches = miller.match_indices(k, ra.miller_indices)
   pairs = matches.pairs()
   assert pairs.column(0).all_eq(flex.size_t_range(k.size()))
   miis_cb = pairs.column(1)
   assert perm.select(miis).all_eq(miis_cb)
Esempio n. 3
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def exercise_optimise_shelxl_weights():
    def calc_goof(fo2, fc, w, k, n_params):
        fc2 = fc.as_intensity_array()
        w = w(fo2.data(), fo2.sigmas(), fc2.data(), k)
        return math.sqrt(
            flex.sum(w * flex.pow2(fo2.data() - k * fc2.data())) /
            (fo2.size() - n_params))

    xs = smtbx.development.sucrose()
    k = 0.05 + 10 * flex.random_double()
    fc = xs.structure_factors(anomalous_flag=False, d_min=0.7).f_calc()
    fo = fc.as_amplitude_array()
    fo = fo.customized_copy(data=fo.data() * math.sqrt(k))
    fo = fo.customized_copy(sigmas=0.03 * fo.data())
    sigmas = fo.sigmas()
    for i in range(fo.size()):
        fo.data()[i] += 2 * scitbx.random.variate(
          scitbx.random.normal_distribution(sigma=sigmas[i]))() \
          + 0.5*random.random()
    fo2 = fo.as_intensity_array()
    fc2 = fc.as_intensity_array()
    w = least_squares.mainstream_shelx_weighting(a=0.1)
    s = calc_goof(fo2, fc, w, k, xs.n_parameters())
    w2 = w.optimise_parameters(fo2, fc2, k, xs.n_parameters())
    s2 = calc_goof(fo2, fc, w2, k, xs.n_parameters())
    # sort data and setup binning by fc/fc_max
    fc_sq = fc.as_intensity_array()
    fc_sq_over_fc_sq_max = fc_sq.data() / flex.max(fc_sq.data())
    permutation = flex.sort_permutation(fc_sq_over_fc_sq_max)
    fc_sq_over_fc_sq_max = fc_sq.customized_copy(
        data=fc_sq_over_fc_sq_max).select(permutation)
    fc_sq = fc_sq.select(permutation)
    fo_sq = fo2.select(permutation)
    n_bins = 10
    bin_max = 0
    bin_limits = flex.size_t(1, 0)
    bin_count = flex.size_t()
    for i in range(n_bins):
        bin_limits.append(int(math.ceil((i + 1) * fc_sq.size() / n_bins)))
        bin_count.append(bin_limits[i + 1] - bin_limits[i])
    goofs_w = flex.double()
    goofs_w2 = flex.double()
    for i_bin in range(n_bins):
        sel = flex.size_t_range(bin_limits[i_bin], bin_limits[i_bin + 1])
        goofs_w2.append(
            calc_goof(fo_sq.select(sel), fc_sq.select(sel), w2, k,
                      xs.n_parameters()))
        goofs_w.append(
            calc_goof(fo_sq.select(sel), fc_sq.select(sel), w, k,
                      xs.n_parameters()))
    a = flex.mean_and_variance(goofs_w).unweighted_sample_variance()
    b = flex.mean_and_variance(goofs_w2).unweighted_sample_variance()
    assert a > b or abs(1 - s) > abs(1 - s2)
    assert a > b  # flat analysis of variance
    assert abs(1 - s) > abs(1 - s2)  # GooF close to 1
Esempio n. 4
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 def e_pot(O, sites_moved):
   if (   O.last_sites_moved is None
       or O.last_sites_moved.id() != sites_moved.id()):
     O.last_sites_moved = sites_moved
     xs = O.fmodels.fmodel_xray().xray_structure
     assert len(sites_moved) == xs.scatterers().size()
     sites_cart = sites_moved
     xs.set_sites_cart(sites_cart=sites_cart)
     O.fmodels.update_xray_structure(update_f_calc=True)
     xs.scatterers().flags_set_grads(state=False)
     xs.scatterers().flags_set_grad_site(
       iselection=flex.size_t_range(xs.scatterers().size()))
     expected_g_size = len(sites_moved) * 3
     if (O.xray_weight_factor is not None):
       tg = O.fmodels.target_and_gradients(
         weights=O.weights,
         compute_gradients=True)
       O.f = tg.target() * O.xray_weight_factor
       O.g = tg.gradients() * O.xray_weight_factor
       assert O.g.size() == expected_g_size
     else:
       O.f = 0.
       O.g = flex.double(expected_g_size, 0)
     if (O.reduced_geo_manager is None):
       reduced_geo_energies = None
     else:
       reduced_geo_energies = O.reduced_geo_manager.energies_sites(
         sites_cart=sites_cart,
         compute_gradients=True)
     other_energies = O.model.restraints_manager.energies_sites(
       sites_cart=sites_cart,
       geometry_flags=cctbx.geometry_restraints.flags.flags(nonbonded=True),
       custom_nonbonded_function=O.custom_nonbonded_function,
       compute_gradients=True)
     nfw = other_energies.normalization_factor * O.weights.w
     O.f += other_energies.target * O.weights.w
     gg = other_energies.gradients * O.weights.w
     if (reduced_geo_energies is not None):
       O.f += reduced_geo_energies.target * nfw
       gg += reduced_geo_energies.gradients * nfw
     assert nfw != 0
     scale = 1 / nfw
     O.last_grms = group_args(
       geo=scale*flex.mean_sq(gg.as_double())**0.5,
       xray=scale*flex.mean_sq(O.g)**0.5,
       real_or_xray="xray")
     xray.minimization.add_gradients(
       scatterers=xs.scatterers(),
       xray_gradients=O.g,
       site_gradients=gg)
     O.f *= scale
     O.g *= scale
     O.last_grms.total = flex.mean_sq(O.g)**0.5
     O.g = flex.vec3_double(O.g)
   return O.f
Esempio n. 5
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 def e_pot(O, sites_moved):
     if (O.last_sites_moved is None
             or O.last_sites_moved.id() != sites_moved.id()):
         O.last_sites_moved = sites_moved
         xs = O.fmodels.fmodel_xray().xray_structure
         assert len(sites_moved) == xs.scatterers().size()
         sites_cart = sites_moved
         xs.set_sites_cart(sites_cart=sites_cart)
         O.fmodels.update_xray_structure(update_f_calc=True)
         xs.scatterers().flags_set_grads(state=False)
         xs.scatterers().flags_set_grad_site(
             iselection=flex.size_t_range(xs.scatterers().size()))
         expected_g_size = len(sites_moved) * 3
         if (O.xray_weight_factor is not None):
             tg = O.fmodels.target_and_gradients(weights=O.weights,
                                                 compute_gradients=True)
             O.f = tg.target() * O.xray_weight_factor
             O.g = tg.gradients() * O.xray_weight_factor
             assert O.g.size() == expected_g_size
         else:
             O.f = 0.
             O.g = flex.double(expected_g_size, 0)
         if (O.reduced_geo_manager is None):
             reduced_geo_energies = None
         else:
             reduced_geo_energies = O.reduced_geo_manager.energies_sites(
                 sites_cart=sites_cart, compute_gradients=True)
         other_energies = O.model.restraints_manager.energies_sites(
             sites_cart=sites_cart,
             geometry_flags=cctbx.geometry_restraints.flags.flags(
                 nonbonded=True),
             custom_nonbonded_function=O.custom_nonbonded_function,
             compute_gradients=True)
         nfw = other_energies.normalization_factor * O.weights.w
         O.f += other_energies.target * O.weights.w
         gg = other_energies.gradients * O.weights.w
         if (reduced_geo_energies is not None):
             O.f += reduced_geo_energies.target * nfw
             gg += reduced_geo_energies.gradients * nfw
         assert nfw != 0
         scale = 1 / nfw
         O.last_grms = group_args(geo=scale *
                                  flex.mean_sq(gg.as_double())**0.5,
                                  xray=scale * flex.mean_sq(O.g)**0.5,
                                  real_or_xray="xray")
         xray.minimization.add_gradients(scatterers=xs.scatterers(),
                                         xray_gradients=O.g,
                                         site_gradients=gg)
         O.f *= scale
         O.g *= scale
         O.last_grms.total = flex.mean_sq(O.g)**0.5
         O.g = flex.vec3_double(O.g)
     return O.f
def exercise_optimise_shelxl_weights():
  def calc_goof(fo2, fc, w, k, n_params):
    fc2 = fc.as_intensity_array()
    w = w(fo2.data(), fo2.sigmas(), fc2.data(), k)
    return math.sqrt(flex.sum(
      w * flex.pow2(fo2.data() - k*fc2.data()))/(fo2.size() - n_params))
  xs = smtbx.development.sucrose()
  k = 0.05 + 10 * flex.random_double()
  fc = xs.structure_factors(anomalous_flag=False, d_min=0.7).f_calc()
  fo = fc.as_amplitude_array()
  fo = fo.customized_copy(data=fo.data()*math.sqrt(k))
  fo = fo.customized_copy(sigmas=0.03*fo.data())
  sigmas = fo.sigmas()
  for i in range(fo.size()):
    fo.data()[i] += 2 * scitbx.random.variate(
      scitbx.random.normal_distribution(sigma=sigmas[i]))() \
      + 0.5*random.random()
  fo2 = fo.as_intensity_array()
  fc2 = fc.as_intensity_array()
  w = least_squares.mainstream_shelx_weighting(a=0.1)
  s = calc_goof(fo2, fc, w, k, xs.n_parameters())
  w2 = w.optimise_parameters(fo2, fc2, k, xs.n_parameters())
  s2 = calc_goof(fo2, fc, w2, k, xs.n_parameters())
  # sort data and setup binning by fc/fc_max
  fc_sq = fc.as_intensity_array()
  fc_sq_over_fc_sq_max = fc_sq.data()/flex.max(fc_sq.data())
  permutation = flex.sort_permutation(fc_sq_over_fc_sq_max)
  fc_sq_over_fc_sq_max = fc_sq.customized_copy(
    data=fc_sq_over_fc_sq_max).select(permutation)
  fc_sq = fc_sq.select(permutation)
  fo_sq = fo2.select(permutation)
  n_bins = 10
  bin_max = 0
  bin_limits = flex.size_t(1, 0)
  bin_count = flex.size_t()
  for i in range(n_bins):
    bin_limits.append(int(math.ceil((i+1) * fc_sq.size()/n_bins)))
    bin_count.append(bin_limits[i+1] - bin_limits[i])
  goofs_w = flex.double()
  goofs_w2 = flex.double()
  for i_bin in range(n_bins):
    sel = flex.size_t_range(bin_limits[i_bin], bin_limits[i_bin+1])
    goofs_w2.append(calc_goof(fo_sq.select(sel),
                              fc_sq.select(sel),
                              w2, k, xs.n_parameters()))
    goofs_w.append(calc_goof(fo_sq.select(sel),
                              fc_sq.select(sel),
                              w, k, xs.n_parameters()))
  a = flex.mean_and_variance(goofs_w).unweighted_sample_variance()
  b = flex.mean_and_variance(goofs_w2).unweighted_sample_variance()
  assert a > b or abs(1-s) > abs(1-s2)
  assert a > b # flat analysis of variance
  assert abs(1-s) > abs(1-s2) # GooF close to 1
Esempio n. 7
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  def optimise_parameters(self, fo_sq, fc_sq,
                          scale_factor, n_independent_params):
    """ Find optimal values of a and b that give a flat analysis of the variance
        when binned by Fc/max(Fc), and a goodness of fit close to 1.

        This is done in a grid search fashion similar to Shelxl.

        self is not modified in place; instead a new instance of the weighting
        scheme is returned.

        It is intended that f_calc should already contain the contribution from
        f_mask (if a solvent mask is used).
    """
    assert fc_sq.is_xray_intensity_array()
    weighting = ext.mainstream_shelx_weighting(a=self.a, b=self.b)

    def compute_chi_sq(fo_sq, fc_sq, a,b):
      weighting.a = a
      weighting.b = b
      weights = weighting(
        fo_sq.data(), fo_sq.sigmas(), fc_sq.data(), scale_factor)
      return (flex.sum(
        weights * flex.pow2(fo_sq.data() - scale_factor * fc_sq.data())))

    fo_sq = fo_sq.deep_copy()
    fo_sq.data().set_selected(fo_sq.data() < 0, 0)

    fo2 = fo_sq.data().deep_copy()
    fo2 /= scale_factor
    sigmas = fo_sq.sigmas() / scale_factor
    sigmas_sq = flex.pow2(sigmas)
    fc2 = fc_sq.data()

    # determine starting values for a and b, formulae taken from shelxl code
    p = (fo2 + 2 * fc2)/3
    p_sq = flex.pow2(p)
    x = flex.sum((flex.pow2(fo2-fc2)-sigmas) * (p_sq/sigmas_sq))
    y = flex.sum( flex.pow2(p_sq)/sigmas_sq)
    z = flex.sum(p)
    start_a = math.sqrt(max(0.0001, 0.64*x/max(1e-8, y)))
    start_b = 0.5 * z * start_a**2 /fo_sq.size()
    a_step = 0.2 * start_a
    b_step = 0.4 * start_b

    # sort data and setup binning by fc/fc_max
    fc_sq_over_fc_sq_max = fc_sq.data()/flex.max(fc_sq.data())
    permutation = flex.sort_permutation(fc_sq_over_fc_sq_max)
    fc_sq_over_fc_sq_max = fc_sq.customized_copy(
      data=fc_sq_over_fc_sq_max).select(permutation)
    fc_sq = fc_sq.select(permutation)
    fo_sq = fo_sq.select(permutation)
    n_bins = 10
    bin_max = 0
    bin_limits = flex.size_t(1, 0)
    bin_count = flex.size_t()
    for i in range(n_bins):
      bin_limits.append(int(math.ceil((i+1) * fc_sq.size()/n_bins)))
      bin_count.append(bin_limits[i+1] - bin_limits[i])

    n = fo_sq.size()//(fo_sq.size()-n_independent_params)

    # search on a 9x9 grid to determine best values of a and b
    gridding = flex.grid(9,9)
    while (a_step > 1e-4 and b_step > 5e-3):
      tmp = flex.double(gridding, 0)
      binned_chi_sq = [tmp.deep_copy() for i in range(n_bins)]
      start_a = max(start_a, 4*a_step) - 4*a_step
      start_b = max(start_b, 4*b_step) - 4*b_step
      for i_bin in range(n_bins):
        sel = flex.size_t_range(bin_limits[i_bin], bin_limits[i_bin+1])
        fc2 = fc_sq.select(sel)
        fo2 = fo_sq.select(sel)
        b = start_b
        for j in range(9):
          a = start_a
          b += b_step
          for k in range(9):
            a += a_step
            binned_chi_sq[i_bin][j,k] += compute_chi_sq(fo2, fc2, a, b)
      min_variance = 9e9
      j_min, k_min = (0, 0)
      for j in range(9):
        for k in range(9):
          variance = 0
          for i_bin in range(n_bins):
            if bin_count[i_bin] == 0: continue
            goof = math.sqrt(binned_chi_sq[i_bin][j,k]*n/bin_count[i_bin])
            variance += (goof-1)**2
          min_variance = min(variance, min_variance)
          if variance == min_variance:
            j_min = j
            k_min = k
      start_a += k_min*a_step
      start_b += j_min*b_step
      if k_min == 8:
        a_step *= 2
        continue
      elif k_min != 0:
        a_step /= 4
      if j_min == 8:
        b_step *= 2
        continue
      elif j_min != 0:
        b_step /=4
      if start_a <= 1e-4: a_step /= 4
      if start_b <= 1e-3: b_step /= 4
    if start_a > 0.2:
      start_a = 0.2
      start_b = 0
    weighting.a = start_a
    weighting.b = start_b
    return weighting
Esempio n. 8
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def exercise(verbose=0):
    distance_ideal = 1.8
    default_vdw_distance = 3.6
    vdw_1_4_factor = 3.5 / 3.6
    sites_cart_manual = flex.vec3_double([(1, 3, 0), (2, 3, 0), (3, 2, 0),
                                          (3, 1, 0), (4, 1, 0), (3, 4, 0),
                                          (4, 3, 0), (5, 3, 0), (6, 2, 0),
                                          (7, 2, 0), (8, 3, 0), (7, 4, 0),
                                          (6, 4, 0), (7, 5, 0), (6, 6, 0),
                                          (8, 6, 0)])
    bond_proxies = geometry_restraints.bond_sorted_asu_proxies(
        asu_mappings=None)
    for i_seqs in [(0, 1), (1, 2), (2, 3), (3, 4), (1, 5), (2, 6), (5, 6),
                   (6, 7), (7, 8), (8, 9), (9, 10), (10, 11), (11, 12),
                   (12, 7), (11, 13), (13, 14), (14, 15), (15, 13)]:
        bond_proxies.process(
            geometry_restraints.bond_simple_proxy(
                i_seqs=i_seqs, distance_ideal=distance_ideal, weight=100))
    angle_proxies = geometry_restraints.shared_angle_proxy()
    for i_seqs, angle_ideal in [[(0, 1, 2), 135], [(0, 1, 5), 135],
                                [(1, 2, 3), 135], [(3, 2, 6), 135],
                                [(2, 3, 4), 120], [(1, 2, 6), 90],
                                [(2, 6, 5), 90], [(6, 5, 1), 90],
                                [(5, 1, 2), 90], [(2, 6, 7), 135],
                                [(5, 6, 7), 135], [(6, 7, 8), 120],
                                [(6, 7, 12), 120], [(7, 8, 9), 120],
                                [(8, 9, 10), 120], [(9, 10, 11), 120],
                                [(10, 11, 12), 120], [(11, 12, 7), 120],
                                [(12, 7, 8), 120], [(10, 11, 13), 120],
                                [(12, 11, 13), 120], [(11, 13, 15), 150],
                                [(11, 13, 14), 150], [(13, 15, 14), 60],
                                [(15, 14, 13), 60], [(14, 13, 15), 60]]:
        angle_proxies.append(
            geometry_restraints.angle_proxy(i_seqs=i_seqs,
                                            angle_ideal=angle_ideal,
                                            weight=1))
    if (0 or verbose):
        dump_pdb(file_name="manual.pdb", sites_cart=sites_cart_manual)
    for traditional_convergence_test in [True, False]:
        for sites_cart_selection in [True, False]:
            sites_cart = sites_cart_manual.deep_copy()
            if sites_cart_selection:
                sites_cart_selection = flex.bool(sites_cart.size(), True)
                sites_cart_selection[1] = False
            assert bond_proxies.asu.size() == 0
            bond_params_table = geometry_restraints.extract_bond_params(
                n_seq=sites_cart.size(),
                bond_simple_proxies=bond_proxies.simple)
            manager = geometry_restraints.manager.manager(
                bond_params_table=bond_params_table,
                angle_proxies=angle_proxies)
            minimized = geometry_restraints.lbfgs.lbfgs(
                sites_cart=sites_cart,
                geometry_restraints_manager=manager,
                lbfgs_termination_params=scitbx.lbfgs.termination_parameters(
                    traditional_convergence_test=traditional_convergence_test,
                    drop_convergence_test_max_drop_eps=1.e-20,
                    drop_convergence_test_iteration_coefficient=1,
                    max_iterations=1000),
                sites_cart_selection=sites_cart_selection,
            )
            assert minimized.minimizer.iter() > 100
            sites_cart_minimized_1 = sites_cart.deep_copy()
            if (0 or verbose):
                dump_pdb(file_name="minimized_1.pdb",
                         sites_cart=sites_cart_minimized_1)
            bond_deltas = geometry_restraints.bond_deltas(
                sites_cart=sites_cart_minimized_1, proxies=bond_proxies.simple)
            angle_deltas = geometry_restraints.angle_deltas(
                sites_cart=sites_cart_minimized_1, proxies=angle_proxies)
            if (0 or verbose):
                for proxy, delta in zip(bond_proxies.simple, bond_deltas):
                    print "bond:", proxy.i_seqs, delta
                for proxy, delta in zip(angle_proxies, angle_deltas):
                    print "angle:", proxy.i_seqs, delta
            assert is_below_limit(value=flex.max(flex.abs(bond_deltas)),
                                  limit=0,
                                  eps=1.e-6)
            assert is_below_limit(value=flex.max(flex.abs(angle_deltas)),
                                  limit=0,
                                  eps=2.e-6)
    sites_cart += matrix.col((1, 1, 0)) - matrix.col(sites_cart.min())
    unit_cell_lengths = list(
        matrix.col(sites_cart.max()) + matrix.col((1, -1.2, 4)))
    unit_cell_lengths[1] *= 2
    unit_cell_lengths[2] *= 2
    xray_structure = xray.structure(crystal_symmetry=crystal.symmetry(
        unit_cell=unit_cell_lengths, space_group_symbol="P112"))
    for serial, site in zip(count(1), sites_cart):
        xray_structure.add_scatterer(
            xray.scatterer(
                label="C%02d" % serial,
                site=xray_structure.unit_cell().fractionalize(site)))
    if (0 or verbose):
        xray_structure.show_summary().show_scatterers()
    p1_structure = (xray_structure.apply_shift(
        (-.5, -.5, 0)).expand_to_p1().apply_shift((.5, .5, 0)))
    for shift in [(1, 0, 0), (0, 1, 0), (0, 0, 1)]:
        p1_structure.add_scatterers(
            p1_structure.apply_shift(shift).scatterers())
    if (0 or verbose):
        open("p1_structure.pdb", "w").write(p1_structure.as_pdb_file())
    nonbonded_cutoff = 6.5
    asu_mappings = xray_structure.asu_mappings(
        buffer_thickness=nonbonded_cutoff)
    bond_asu_table = crystal.pair_asu_table(asu_mappings=asu_mappings)
    geometry_restraints.add_pairs(bond_asu_table, bond_proxies.simple)
    shell_asu_tables = crystal.coordination_sequences.shell_asu_tables(
        pair_asu_table=bond_asu_table, max_shell=3)
    shell_sym_tables = [
        shell_asu_table.extract_pair_sym_table()
        for shell_asu_table in shell_asu_tables
    ]
    bond_params_table = geometry_restraints.extract_bond_params(
        n_seq=sites_cart.size(), bond_simple_proxies=bond_proxies.simple)
    atom_energy_types = flex.std_string(sites_cart.size(), "Default")
    nonbonded_params = geometry_restraints.nonbonded_params(
        factor_1_4_interactions=vdw_1_4_factor,
        const_shrink_1_4_interactions=0,
        default_distance=default_vdw_distance)
    nonbonded_params.distance_table.setdefault(
        "Default")["Default"] = default_vdw_distance
    pair_proxies = geometry_restraints.pair_proxies(
        bond_params_table=bond_params_table,
        shell_asu_tables=shell_asu_tables,
        model_indices=None,
        conformer_indices=None,
        nonbonded_params=nonbonded_params,
        nonbonded_types=atom_energy_types,
        nonbonded_distance_cutoff_plus_buffer=nonbonded_cutoff)
    if (0 or verbose):
        print "pair_proxies.bond_proxies.n_total():", \
               pair_proxies.bond_proxies.n_total(),
        print "simple:", pair_proxies.bond_proxies.simple.size(),
        print "sym:", pair_proxies.bond_proxies.asu.size()
        print "pair_proxies.nonbonded_proxies.n_total():", \
               pair_proxies.nonbonded_proxies.n_total(),
        print "simple:", pair_proxies.nonbonded_proxies.simple.size(),
        print "sym:", pair_proxies.nonbonded_proxies.asu.size()
        print "min_distance_nonbonded: %.2f" % flex.min(
            geometry_restraints.nonbonded_deltas(
                sites_cart=sites_cart,
                sorted_asu_proxies=pair_proxies.nonbonded_proxies))
    s = StringIO()
    pair_proxies.bond_proxies.show_histogram_of_model_distances(
        sites_cart=sites_cart, f=s, prefix="[]")
    assert s.getvalue().splitlines()[0] == "[]Histogram of bond lengths:"
    assert s.getvalue().splitlines()[5].startswith("[]      1.80 -     1.80:")
    s = StringIO()
    pair_proxies.bond_proxies.show_histogram_of_deltas(sites_cart=sites_cart,
                                                       f=s,
                                                       prefix="][")
    assert s.getvalue().splitlines()[0] == "][Histogram of bond deltas:"
    assert s.getvalue().splitlines()[5].startswith("][     0.000 -    0.000:")
    s = StringIO()
    pair_proxies.bond_proxies.show_sorted(by_value="residual",
                                          sites_cart=sites_cart,
                                          max_items=3,
                                          f=s,
                                          prefix=":;")
    l = s.getvalue().splitlines()
    assert l[0] == ":;Bond restraints: 18"
    assert l[1] == ":;Sorted by residual:"
    assert l[2].startswith(":;bond ")
    assert l[3].startswith(":;     ")
    assert l[4] == ":;  ideal  model  delta    sigma   weight residual"
    for i in [5, -2]:
        assert l[i].startswith(":;  1.800  1.800 ")
    assert l[-1] == ":;... (remaining 15 not shown)"
    s = StringIO()
    pair_proxies.nonbonded_proxies.show_histogram_of_model_distances(
        sites_cart=sites_cart, f=s, prefix="]^")
    assert not show_diff(
        s.getvalue(), """\
]^Histogram of nonbonded interaction distances:
]^      2.16 -     3.03: 3
]^      3.03 -     3.89: 12
]^      3.89 -     4.75: 28
]^      4.75 -     5.61: 44
]^      5.61 -     6.48: 54
""")
    s = StringIO()
    pair_proxies.nonbonded_proxies.show_sorted(by_value="delta",
                                               sites_cart=sites_cart,
                                               max_items=7,
                                               f=s,
                                               prefix=">,")
    assert not show_diff(s.getvalue(),
                         """\
>,Nonbonded interactions: 141
>,Sorted by model distance:
>,nonbonded 15
>,          15
>,   model   vdw sym.op.
>,   2.164 3.600 -x+2,-y+1,z
...
>,nonbonded 4
>,          8
>,   model   vdw
>,   3.414 3.600
>,... (remaining 134 not shown)
""",
                         selections=[range(6), range(-5, 0)])
    vdw_1_sticks = []
    vdw_2_sticks = []
    for proxy in pair_proxies.nonbonded_proxies.simple:
        if (proxy.vdw_distance == default_vdw_distance):
            vdw_1_sticks.append(
                pml_stick(begin=sites_cart[proxy.i_seqs[0]],
                          end=sites_cart[proxy.i_seqs[1]]))
        else:
            vdw_2_sticks.append(
                pml_stick(begin=sites_cart[proxy.i_seqs[0]],
                          end=sites_cart[proxy.i_seqs[1]]))
    mps = asu_mappings.mappings()
    for proxy in pair_proxies.nonbonded_proxies.asu:
        if (proxy.vdw_distance == default_vdw_distance):
            vdw_1_sticks.append(
                pml_stick(begin=mps[proxy.i_seq][0].mapped_site(),
                          end=mps[proxy.j_seq][proxy.j_sym].mapped_site()))
        else:
            vdw_2_sticks.append(
                pml_stick(begin=mps[proxy.i_seq][0].mapped_site(),
                          end=mps[proxy.j_seq][proxy.j_sym].mapped_site()))
    if (0 or verbose):
        pml_write(f=open("vdw_1.pml", "w"), label="vdw_1", sticks=vdw_1_sticks)
        pml_write(f=open("vdw_2.pml", "w"), label="vdw_2", sticks=vdw_2_sticks)
    #
    i_pdb = count(2)
    for use_crystal_symmetry in [False, True]:
        if (not use_crystal_symmetry):
            crystal_symmetry = None
            site_symmetry_table = None
        else:
            crystal_symmetry = xray_structure
            site_symmetry_table = xray_structure.site_symmetry_table()
        for sites_cart in [
                sites_cart_manual.deep_copy(),
                sites_cart_minimized_1.deep_copy()
        ]:
            manager = geometry_restraints.manager.manager(
                crystal_symmetry=crystal_symmetry,
                site_symmetry_table=site_symmetry_table,
                nonbonded_params=nonbonded_params,
                nonbonded_types=atom_energy_types,
                nonbonded_function=geometry_restraints.
                prolsq_repulsion_function(),
                bond_params_table=bond_params_table,
                shell_sym_tables=shell_sym_tables,
                nonbonded_distance_cutoff=nonbonded_cutoff,
                nonbonded_buffer=1,
                angle_proxies=angle_proxies,
                plain_pairs_radius=5)
            manager = manager.select(
                selection=flex.bool(sites_cart.size(), True))
            manager = manager.select(iselection=flex.size_t_range(
                stop=sites_cart.size()))
            pair_proxies = manager.pair_proxies(sites_cart=sites_cart)
            minimized = geometry_restraints.lbfgs.lbfgs(
                sites_cart=sites_cart,
                geometry_restraints_manager=manager,
                lbfgs_termination_params=scitbx.lbfgs.termination_parameters(
                    max_iterations=1000))
            if (0 or verbose):
                minimized.final_target_result.show()
                print "number of function evaluations:", minimized.minimizer.nfun(
                )
                print "n_updates_pair_proxies:", manager.n_updates_pair_proxies
            if (not use_crystal_symmetry):
                assert minimized.final_target_result.bond_residual_sum < 1.e-3
                assert minimized.final_target_result.nonbonded_residual_sum < 0.1
            else:
                assert minimized.final_target_result.bond_residual_sum < 1.e-2
                assert minimized.final_target_result.nonbonded_residual_sum < 0.1
            assert minimized.final_target_result.angle_residual_sum < 1.e-3
            if (0 or verbose):
                pdb_file_name = "minimized_%d.pdb" % i_pdb.next()
                print "Writing file:", pdb_file_name
                dump_pdb(file_name=pdb_file_name, sites_cart=sites_cart)
            if (manager.site_symmetry_table is None):
                additional_site_symmetry_table = None
            else:
                additional_site_symmetry_table = sgtbx.site_symmetry_table()
            assert manager.new_including_isolated_sites(
              n_additional_sites=0,
              site_symmetry_table=additional_site_symmetry_table,
              nonbonded_types=flex.std_string()).plain_pairs_radius \
                == manager.plain_pairs_radius
            if (crystal_symmetry is not None):
                assert len(manager.plain_pair_sym_table) == 16
                if (0 or verbose):
                    manager.plain_pair_sym_table.show()
    #
    xray_structure.set_u_iso(values=flex.double([
        0.77599982480241358, 0.38745781137212021, 0.20667558236418682,
        0.99759840171302094, 0.8917287406687805, 0.64780251325379845,
        0.24878590382983534, 0.59480621182194615, 0.58695637792905142,
        0.33997130213653637, 0.51258699130743735, 0.79760289141276675,
        0.39996577657875021, 0.4329328819341467, 0.70422156561726479,
        0.87260110626999332
    ]))

    class parameters:
        pass

    parameters.sphere_radius = 5
    parameters.distance_power = 0.7
    parameters.average_power = 0.9
    parameters.wilson_b_weight = 1.3952
    parameters.wilson_b_weight_auto = False
    adp_energies = adp_restraints.energies_iso(
        geometry_restraints_manager=manager,
        xray_structure=xray_structure,
        parameters=parameters,
        wilson_b=None,
        use_hd=False,
        use_u_local_only=False,
        compute_gradients=False,
        gradients=None,
        normalization=False,
        collect=True)
    assert adp_energies.number_of_restraints == 69
    assert approx_equal(adp_energies.residual_sum, 6.24865382467)
    assert adp_energies.gradients is None
    assert adp_energies.u_i.size() == adp_energies.number_of_restraints
    assert adp_energies.u_j.size() == adp_energies.number_of_restraints
    assert adp_energies.r_ij.size() == adp_energies.number_of_restraints
    for wilson_b in [None, 10, 100]:
        finite_difference_gradients = flex.double()
        eps = 1.e-6
        for i_scatterer in xrange(xray_structure.scatterers().size()):
            rs = []
            for signed_eps in [eps, -eps]:
                xray_structure_eps = xray_structure.deep_copy_scatterers()
                xray_structure_eps.scatterers(
                )[i_scatterer].u_iso += signed_eps
                adp_energies = adp_restraints.energies_iso(
                    geometry_restraints_manager=manager,
                    xray_structure=xray_structure_eps,
                    parameters=parameters,
                    wilson_b=wilson_b,
                    use_u_local_only=False,
                    use_hd=False,
                    compute_gradients=True,
                    gradients=None,
                    normalization=False,
                    collect=False)
                rs.append(adp_energies.residual_sum)
                assert adp_energies.gradients.size() \
                    == xray_structure.scatterers().size()
                assert adp_energies.u_i == None
                assert adp_energies.u_j == None
                assert adp_energies.r_ij == None
            finite_difference_gradients.append((rs[0] - rs[1]) / (2 * eps))
        sel = flex.bool(xray_structure.scatterers().size(), True)
        xray_structure.scatterers().flags_set_grad_u_iso(sel.iselection())
        adp_energies = adp_restraints.energies_iso(
            geometry_restraints_manager=manager,
            xray_structure=xray_structure,
            parameters=parameters,
            wilson_b=wilson_b,
            use_u_local_only=False,
            use_hd=False,
            compute_gradients=True,
            gradients=None,
            normalization=False,
            collect=False)
        assert approx_equal(adp_energies.gradients,
                            finite_difference_gradients)
    print "OK"
def exercise_affine_occupancy_parameter():
    xs = xray.structure(crystal_symmetry=crystal.symmetry(
        unit_cell=(), space_group_symbol='hall: P 1'),
                        scatterers=flex.xray_scatterer((
                            xray.scatterer('C0', occupancy=1),
                            xray.scatterer('C1', occupancy=1),
                            xray.scatterer('C2', occupancy=1),
                            xray.scatterer('C3', occupancy=1),
                        )))
    sc = xs.scatterers()
    sc.flags_set_grad_occupancy(flex.size_t_range(4))

    # Two occupancies adding up to 1 (most common case of disorder)
    r = constraints.ext.reparametrisation(xs.unit_cell())
    occ_1 = r.add(constraints.independent_occupancy_parameter, sc[1])
    occ_3 = r.add(constraints.affine_asu_occupancy_parameter,
                  dependee=occ_1,
                  a=-1,
                  b=1,
                  scatterer=sc[3])
    r.finalise()
    r.linearise()
    assert approx_equal(occ_1.value, 1)
    assert approx_equal(occ_3.value, 0)
    jt0 = sparse.matrix(
        1,
        2,
        [
            {
                0: 1
            },  # 1st col = derivatives of occ_1
            {
                0: -1
            },  # 2nd col = derivatives of occ_3
        ])
    assert sparse.approx_equal(tolerance=1e-15)(r.jacobian_transpose, jt0)

    # Example illustrating the instruction SUMP in SHELX 97 manual (p. 7-26)
    # We disregard the issue of the special position which is orthogonal to the
    # point we want to test here.
    xs = xray.structure(crystal_symmetry=crystal.symmetry(
        unit_cell=(), space_group_symbol='hall: P 1'),
                        scatterers=flex.xray_scatterer((
                            xray.scatterer('Na+', occupancy=1),
                            xray.scatterer('Ca2+', occupancy=1),
                            xray.scatterer('Al3+', occupancy=0.35),
                            xray.scatterer('K+', occupancy=0.15),
                        )))
    sc = xs.scatterers()
    sc.flags_set_grad_occupancy(flex.size_t_range(4))

    # The constraints are:
    # fully occupied: occ(Na+) + occ(Ca2+) + occ(Al3+) + occ(K+) = 1
    # average charge +2: occ(Na+) + 2 occ(Ca2+) + 3 occ(Al3+) + occ(K+) = +2
    # This can be solved as:
    # occ(Na+)  = occ(Al3+) - occ(K+)
    # occ(Ca2+) = 1 - 2 occ(Al3+)
    r = constraints.ext.reparametrisation(xs.unit_cell())
    occ_Al = r.add(constraints.independent_occupancy_parameter, sc[2])
    occ_K = r.add(constraints.independent_occupancy_parameter, sc[3])
    occ_Na = r.add(constraints.affine_asu_occupancy_parameter,
                   occ_Al,
                   1,
                   occ_K,
                   -1,
                   0,
                   scatterer=sc[0])
    occ_Ca = r.add(constraints.affine_asu_occupancy_parameter,
                   occ_Al,
                   -2,
                   1,
                   scatterer=sc[1])
    r.finalise()
    r.linearise()
    assert approx_equal(occ_Na.value, 0.2)
    assert approx_equal(occ_Ca.value, 0.3)
    assert approx_equal(occ_Al.value, 0.35)
    assert approx_equal(occ_K.value, 0.15)
    jt0 = sparse.matrix(
        2,
        4,
        [
            {
                0: 1
            },  # diff occ(Al3+)
            {
                1: 1
            },  # diff occ(K+)
            {
                0: 1,
                1: -1
            },  # diff occ(Na+)
            {
                0: -2
            },  # diff occ(Ca2+)
        ])
    assert sparse.approx_equal(tolerance=1e-15)(r.jacobian_transpose, jt0)
def exercise_floating_origin_dynamic_weighting(verbose=False):
  from cctbx import covariance
  import scitbx.math

  worst_condition_number_acceptable = 10

  # light elements only
  xs0 = random_structure.xray_structure(elements=['C', 'C', 'C', 'O', 'N'],
                                        use_u_aniso=True)
  msg = "light elements in %s ..." % (
    xs0.space_group_info().type().hall_symbol())
  if verbose:
    print(msg, end=' ')
  fo_sq = xs0.structure_factors(d_min=0.8).f_calc().norm()
  fo_sq = fo_sq.customized_copy(sigmas=flex.double(fo_sq.size(), 1.))
  xs = xs0.deep_copy_scatterers()
  xs.shake_adp()
  xs.shake_sites_in_place(rms_difference=0.1)
  for sc in xs.scatterers():
    sc.flags.set_grad_site(True).set_grad_u_aniso(True)
  ls = least_squares.crystallographic_ls(
    fo_sq.as_xray_observations(),
    constraints.reparametrisation(
      structure=xs,
      constraints=[],
      connectivity_table=smtbx.utils.connectivity_table(xs)),
    weighting_scheme=least_squares.unit_weighting(),
    origin_fixing_restraints_type=
    origin_fixing_restraints.atomic_number_weighting)
  ls.build_up()
  lambdas = eigensystem.real_symmetric(
    ls.normal_matrix_packed_u().matrix_packed_u_as_symmetric()).values()
  # assert the restrained L.S. problem is not too ill-conditionned
  cond = math.log10(lambdas[0]/lambdas[-1])
  if verbose:
    print("normal matrix condition: %.1f" % cond)
  assert cond < worst_condition_number_acceptable, msg

  # one heavy element
  xs0 = random_structure.xray_structure(
    space_group_info=sgtbx.space_group_info('hall: P 2yb'),
    elements=['Zn', 'C', 'C', 'C', 'O', 'N'],
    use_u_aniso=True)
  msg = "one heavy element + light elements (synthetic data) in %s ..." % (
    xs0.space_group_info().type().hall_symbol())
  if verbose:
    print(msg, end=' ')
  fo_sq = xs0.structure_factors(d_min=0.8).f_calc().norm()
  fo_sq = fo_sq.customized_copy(sigmas=flex.double(fo_sq.size(), 1.))
  xs = xs0.deep_copy_scatterers()
  xs.shake_adp()
  xs.shake_sites_in_place(rms_difference=0.1)
  for sc in xs.scatterers():
    sc.flags.set_grad_site(True).set_grad_u_aniso(True)
  ls = least_squares.crystallographic_ls(
    fo_sq.as_xray_observations(),
    constraints.reparametrisation(
      structure=xs,
      constraints=[],
      connectivity_table=smtbx.utils.connectivity_table(xs)),
    weighting_scheme=least_squares.mainstream_shelx_weighting(),
    origin_fixing_restraints_type=
    origin_fixing_restraints.atomic_number_weighting)
  ls.build_up()
  lambdas = eigensystem.real_symmetric(
    ls.normal_matrix_packed_u().matrix_packed_u_as_symmetric()).values()
  # assert the restrained L.S. problem is not too ill-conditionned
  cond = math.log10(lambdas[0]/lambdas[-1])
  if verbose:
    print("normal matrix condition: %.1f" % cond)
  assert cond < worst_condition_number_acceptable, msg

  # are esd's for x,y,z coordinates of the same order of magnitude?
  var_cart = covariance.orthogonalize_covariance_matrix(
    ls.covariance_matrix(),
    xs.unit_cell(),
    xs.parameter_map())
  var_site_cart = covariance.extract_covariance_matrix_for_sites(
      flex.size_t_range(len(xs.scatterers())),
      var_cart,
      xs.parameter_map())
  site_esds = var_site_cart.matrix_packed_u_diagonal()
  indicators = flex.double()
  for i in xrange(0, len(site_esds), 3):
    stats = scitbx.math.basic_statistics(site_esds[i:i+3])
    indicators.append(stats.bias_corrected_standard_deviation/stats.mean)
  assert indicators.all_lt(2)

  # especially troublesome structure with one heavy element
  # (contributed by Jonathan Coome)
  xs0 = xray.structure(
    crystal_symmetry=crystal.symmetry(
      unit_cell=(8.4519, 8.4632, 18.7887, 90, 96.921, 90),
      space_group_symbol="hall: P 2yb"),
    scatterers=flex.xray_scatterer([
      xray.scatterer( #0
                      label="ZN1",
                      site=(-0.736683, -0.313978, -0.246902),
                      u=(0.000302, 0.000323, 0.000054,
                         0.000011, 0.000015, -0.000004)),
      xray.scatterer( #1
                      label="N3B",
                      site=(-0.721014, -0.313583, -0.134277),
                      u=(0.000268, 0.000237, 0.000055,
                         -0.000027, 0.000005, 0.000006)),
      xray.scatterer( #2
                      label="N3A",
                      site=(-0.733619, -0.290423, -0.357921),
                      u=(0.000229, 0.000313, 0.000053,
                         0.000022, 0.000018, -0.000018)),
      xray.scatterer( #3
                      label="C9B",
                      site=(-1.101537, -0.120157, -0.138063),
                      u=(0.000315, 0.000345, 0.000103,
                         0.000050, 0.000055, -0.000017)),
    xray.scatterer( #4
                    label="N5B",
                    site=(-0.962032, -0.220345, -0.222045),
                    u=(0.000274, 0.000392, 0.000060,
                       -0.000011, -0.000001, -0.000002)),
    xray.scatterer( #5
                    label="N1B",
                    site=(-0.498153, -0.402742, -0.208698),
                    u=(0.000252, 0.000306, 0.000063,
                       0.000000, 0.000007, 0.000018)),
    xray.scatterer( #6
                    label="C3B",
                    site=(-0.322492, -0.472610, -0.114594),
                    u=(0.000302, 0.000331, 0.000085,
                       0.000016, -0.000013, 0.000037)),
    xray.scatterer( #7
                    label="C4B",
                    site=(-0.591851, -0.368163, -0.094677),
                    u=(0.000262, 0.000255, 0.000073,
                       -0.000034, 0.000027, -0.000004)),
    xray.scatterer( #8
                    label="N4B",
                    site=(-0.969383, -0.204624, -0.150014),
                    u=(0.000279, 0.000259, 0.000070,
                       -0.000009, 0.000039, 0.000000)),
    xray.scatterer( #9
                    label="N2B",
                    site=(-0.470538, -0.414572, -0.135526),
                    u=(0.000277, 0.000282, 0.000065,
                       0.000003, 0.000021, -0.000006)),
    xray.scatterer( #10
                    label="C8A",
                    site=(-0.679889, -0.158646, -0.385629),
                    u=(0.000209, 0.000290, 0.000078,
                       0.000060, 0.000006, 0.000016)),
    xray.scatterer( #11
                    label="N5A",
                    site=(-0.649210, -0.075518, -0.263412),
                    u=(0.000307, 0.000335, 0.000057,
                       -0.000002, 0.000016, -0.000012)),
    xray.scatterer( #12
                    label="C6B",
                    site=(-0.708620, -0.325965, 0.011657),
                    u=(0.000503, 0.000318, 0.000053,
                       -0.000058, 0.000032, -0.000019)),
    xray.scatterer( #13
                    label="C10B",
                    site=(-1.179332, -0.083184, -0.202815),
                    u=(0.000280, 0.000424, 0.000136,
                       0.000094, 0.000006, 0.000013)),
    xray.scatterer( #14
                    label="N1A",
                    site=(-0.838363, -0.532191, -0.293213),
                    u=(0.000312, 0.000323, 0.000060,
                       0.000018, 0.000011, -0.000008)),
    xray.scatterer( #15
                    label="C3A",
                    site=(-0.915414, -0.671031, -0.393826),
                    u=(0.000319, 0.000384, 0.000078,
                       -0.000052, -0.000001, -0.000020)),
    xray.scatterer( #16
                    label="C1A",
                    site=(-0.907466, -0.665419, -0.276011),
                    u=(0.000371, 0.000315, 0.000079,
                       0.000006, 0.000036, 0.000033)),
    xray.scatterer( #17
                    label="C1B",
                    site=(-0.365085, -0.452753, -0.231927),
                    u=(0.000321, 0.000253, 0.000087,
                       -0.000024, 0.000047, -0.000034)),
    xray.scatterer( #18
                    label="C11A",
                    site=(-0.598622, 0.053343, -0.227354),
                    u=(0.000265, 0.000409, 0.000084,
                       0.000088, -0.000018, -0.000030)),
    xray.scatterer( #19
                    label="C2A",
                    site=(-0.958694, -0.755645, -0.337016),
                    u=(0.000394, 0.000350, 0.000106,
                       -0.000057, 0.000027, -0.000005)),
    xray.scatterer( #20
                    label="C4A",
                    site=(-0.784860, -0.407601, -0.402050),
                    u=(0.000238, 0.000296, 0.000064,
                       0.000002, 0.000011, -0.000016)),
    xray.scatterer( #21
                    label="C5A",
                    site=(-0.784185, -0.399716, -0.475491),
                    u=(0.000310, 0.000364, 0.000062,
                       0.000044, -0.000011, -0.000017)),
    xray.scatterer( #22
                    label="N4A",
                    site=(-0.630284, -0.043981, -0.333143),
                    u=(0.000290, 0.000275, 0.000074,
                       0.000021, 0.000027, 0.000013)),
    xray.scatterer( #23
                    label="C10A",
                    site=(-0.545465, 0.166922, -0.272829),
                    u=(0.000369, 0.000253, 0.000117,
                       0.000015, -0.000002, -0.000008)),
    xray.scatterer( #24
                    label="C9A",
                    site=(-0.567548, 0.102272, -0.339923),
                    u=(0.000346, 0.000335, 0.000103,
                       -0.000016, 0.000037, 0.000023)),
    xray.scatterer( #25
                    label="C11B",
                    site=(-1.089943, -0.146930, -0.253779),
                    u=(0.000262, 0.000422, 0.000102,
                       -0.000018, -0.000002, 0.000029)),
    xray.scatterer( #26
                    label="N2A",
                    site=(-0.843385, -0.537780, -0.366515),
                    u=(0.000273, 0.000309, 0.000055,
                       -0.000012, -0.000005, -0.000018)),
    xray.scatterer( #27
                    label="C7A",
                    site=(-0.674021, -0.136086, -0.457790),
                    u=(0.000362, 0.000378, 0.000074,
                       0.000043, 0.000034, 0.000016)),
    xray.scatterer( #28
                    label="C8B",
                    site=(-0.843625, -0.264182, -0.102023),
                    u=(0.000264, 0.000275, 0.000072,
                       -0.000025, 0.000019, -0.000005)),
    xray.scatterer( #29
                    label="C6A",
                    site=(-0.726731, -0.261702, -0.502366),
                    u=(0.000339, 0.000472, 0.000064,
                       0.000062, -0.000003, 0.000028)),
    xray.scatterer( #30
                    label="C5B",
                    site=(-0.577197, -0.376753, -0.020800),
                    u=(0.000349, 0.000353, 0.000066,
                       -0.000082, -0.000022, 0.000014)),
    xray.scatterer( #31
                    label="C2B",
                    site=(-0.252088, -0.497338, -0.175057),
                    u=(0.000251, 0.000342, 0.000119,
                       0.000020, 0.000034, -0.000018)),
    xray.scatterer( #32
                    label="C7B",
                    site=(-0.843956, -0.268811, -0.028080),
                    u=(0.000344, 0.000377, 0.000078,
                       -0.000029, 0.000059, -0.000007)),
    xray.scatterer( #33
                    label="F4B",
                    site=(-0.680814, -0.696808, -0.115056),
                    u=(0.000670, 0.000408, 0.000109,
                       -0.000099, 0.000139, -0.000031)),
    xray.scatterer( #34
                    label="F1B",
                    site=(-0.780326, -0.921249, -0.073962),
                    u=(0.000687, 0.000357, 0.000128,
                       -0.000152, -0.000011, 0.000021)),
    xray.scatterer( #35
                    label="B1B",
                    site=(-0.795220, -0.758128, -0.075955),
                    u=(0.000413, 0.000418, 0.000075,
                       0.000054, 0.000045, 0.000023)),
    xray.scatterer( #36
                    label="F2B",
                    site=(-0.945140, -0.714626, -0.105820),
                    u=(0.000584, 0.001371, 0.000108,
                       0.000420, 0.000067, 0.000134)),
    xray.scatterer( #37
                    label="F3B",
                    site=(-0.768914, -0.701660, -0.005161),
                    u=(0.000678, 0.000544, 0.000079,
                       -0.000000, 0.000090, -0.000021)),
    xray.scatterer( #38
                    label="F1A",
                    site=(-0.109283, -0.252334, -0.429288),
                    u=(0.000427, 0.001704, 0.000125,
                       0.000407, 0.000041, 0.000035)),
    xray.scatterer( #39
                    label="F4A",
                    site=(-0.341552, -0.262864, -0.502023),
                    u=(0.000640, 0.000557, 0.000081,
                       -0.000074, 0.000042, -0.000052)),
    xray.scatterer( #40
                    label="F3A",
                    site=(-0.324533, -0.142292, -0.393215),
                    u=(0.000471, 0.001203, 0.000134,
                       0.000333, -0.000057, -0.000220)),
    xray.scatterer( #41
                    label="F2A",
                    site=(-0.312838, -0.405405, -0.400231),
                    u=(0.002822, 0.000831, 0.000092,
                       -0.000648, 0.000115, 0.000027)),
    xray.scatterer( #42
                    label="B1A",
                    site=(-0.271589, -0.268874, -0.430724),
                    u=(0.000643, 0.000443, 0.000079,
                       0.000040, 0.000052, -0.000034)),
    xray.scatterer( #43
                    label="H5B",
                    site=(-0.475808, -0.413802, 0.004402),
                    u=0.005270),
    xray.scatterer( #44
                    label="H6B",
                    site=(-0.699519, -0.326233, 0.062781),
                    u=0.019940),
    xray.scatterer( #45
                    label="H3B",
                    site=(-0.283410, -0.484757, -0.063922),
                    u=0.029990),
    xray.scatterer( #46
                    label="H1B",
                    site=(-0.357103, -0.451819, -0.284911),
                    u=0.031070),
    xray.scatterer( #47
                    label="H10A",
                    site=(-0.495517, 0.268296, -0.256187),
                    u=0.027610),
    xray.scatterer( #48
                    label="H2B",
                    site=(-0.147129, -0.535141, -0.174699),
                    u=0.017930),
    xray.scatterer( #49
                    label="H7A",
                    site=(-0.643658, -0.031387, -0.475357),
                    u=0.020200),
    xray.scatterer( #50
                    label="H1A",
                    site=(-0.912757, -0.691043, -0.227554),
                    u=0.033320),
    xray.scatterer( #51
                    label="H7B",
                    site=(-0.933670, -0.241189, -0.010263),
                    u=0.021310),
    xray.scatterer( #52
                    label="H11B",
                    site=(-1.107736, -0.155470, -0.311996),
                    u=0.041500),
    xray.scatterer( #53
                    label="H9A",
                    site=(-0.539908, 0.139753, -0.382281),
                    u=0.007130),
    xray.scatterer( #54
                    label="H10B",
                    site=(-1.265944, -0.029610, -0.212398),
                    u=0.030910),
    xray.scatterer( #55
                    label="H3A",
                    site=(-0.934728, -0.691149, -0.450551),
                    u=0.038950),
    xray.scatterer( #56
                    label="H5A",
                    site=(-0.833654, -0.487479, -0.508239),
                    u=0.031150),
    xray.scatterer( #57
                    label="H6A",
                    site=(-0.742871, -0.242269, -0.558157),
                    u=0.050490),
    xray.scatterer( #58
                    label="H9B",
                    site=(-1.120150, -0.093752, -0.090706),
                    u=0.039310),
    xray.scatterer( #59
                    label="H11A",
                    site=(-0.593074, 0.054973, -0.180370),
                    u=0.055810),
    xray.scatterer( #60
                    label="H2A",
                    site=(-0.999576, -0.842158, -0.340837),
                    u=0.057030)
    ]))
  fo_sq = xs0.structure_factors(d_min=0.8).f_calc().norm()
  fo_sq = fo_sq.customized_copy(sigmas=flex.double(fo_sq.size(), 1.))
  for hydrogen_flag in (True, False):
    xs = xs0.deep_copy_scatterers()
    if not hydrogen_flag:
      xs.select_inplace(~xs.element_selection('H'))
    xs.shake_adp()
    xs.shake_sites_in_place(rms_difference=0.1)
    for sc in xs.scatterers():
      sc.flags.set_grad_site(True).set_grad_u_aniso(False)
    ls = least_squares.crystallographic_ls(
      fo_sq.as_xray_observations(),
      constraints.reparametrisation(
        structure=xs,
        constraints=[],
        connectivity_table=smtbx.utils.connectivity_table(xs)),
      weighting_scheme=least_squares.unit_weighting(),
      origin_fixing_restraints_type=
      origin_fixing_restraints.atomic_number_weighting)

    ls.build_up()
    lambdas = eigensystem.real_symmetric(
      ls.normal_matrix_packed_u().matrix_packed_u_as_symmetric()).values()
    # assert the restrained L.S. problem is not too ill-conditionned
    cond = math.log10(lambdas[0]/lambdas[-1])
    msg = ("one heavy element + light elements (real data) %s Hydrogens: %.1f"
           % (['without', 'with'][hydrogen_flag], cond))
    if verbose: print(msg)
    assert cond < worst_condition_number_acceptable, msg


    # are esd's for x,y,z coordinates of the same order of magnitude?
    var_cart = covariance.orthogonalize_covariance_matrix(
      ls.covariance_matrix(),
      xs.unit_cell(),
      xs.parameter_map())
    var_site_cart = covariance.extract_covariance_matrix_for_sites(
        flex.size_t_range(len(xs.scatterers())),
        var_cart,
        xs.parameter_map())
    site_esds = var_site_cart.matrix_packed_u_diagonal()
    indicators = flex.double()
    for i in xrange(0, len(site_esds), 3):
      stats = scitbx.math.basic_statistics(site_esds[i:i+3])
      indicators.append(stats.bias_corrected_standard_deviation/stats.mean)
    assert indicators.all_lt(1)
Esempio n. 11
0
def exercise_hl_ab_only(anomalous_flag):
    cs = crystal.symmetry(unit_cell=(3.95738, 5.1446, 6.72755, 83, 109, 129),
                          space_group_symbol="P1")
    if (not anomalous_flag):
        i = [(-1, 0, 1), (-1, 1, 1), (0, -1, 1), (0, 0, 1), (0, 0, 2),
             (0, 1, 0), (0, 1, 1), (1, -1, 0)]
    else:
        i = [(-1, 0, 1), (1, 0, -1), (-1, 1, 1), (1, -1, -1), (0, -1, 1),
             (0, 1, -1), (0, 0, 1), (0, 0, -1), (0, 0, 2), (0, 0, -2),
             (0, 1, 0), (0, -1, 0), (0, 1, 1), (0, -1, -1), (1, -1, 0),
             (-1, 1, 0)]
    ms = miller.set(crystal_symmetry=cs,
                    indices=flex.miller_index(i),
                    anomalous_flag=anomalous_flag)
    ma = ms.array(data=flex.size_t_range(ms.indices().size()).as_double() + 1)
    mtz_dataset = ma.as_mtz_dataset(column_root_label="HA")
    columns = mtz_dataset.columns()
    if (not anomalous_flag):
        assert columns.size() == 4
        c = columns[3]
        assert c.label() == "HA"
        c.set_type("A")
        values = c.extract_values()
        selection_valid = c.selection_valid()
        c = mtz_dataset.add_column(label="HB", type="A")
        c.set_values(values=-values, selection_valid=selection_valid)
    else:
        assert columns.size() == 5
        for i, l in [(3, "HA(+)"), (4, "HA(-)")]:
            c = columns[i]
            assert c.label() == l
            if (i == 4):
                c.set_label("HB(+)")
            c.set_type("A")
        for i, l in [(3, "HA(-)"), (4, "HB(-)")]:
            c = columns[i]
            values = c.extract_values()
            selection_valid = c.selection_valid()
            c = mtz_dataset.add_column(label=l, type="A")
            c.set_values(values=-values, selection_valid=selection_valid)
    mtz_obj = mtz_dataset.mtz_object()
    mas = mtz_obj.as_miller_arrays()
    assert len(mas) == 1
    assert approx_equal(mas[0].indices(), ma.indices())
    if (not anomalous_flag):
        assert approx_equal(mas[0].data(), [(1, -1, 0, 0), (2, -2, 0, 0),
                                            (3, -3, 0, 0), (4, -4, 0, 0),
                                            (5, -5, 0, 0), (6, -6, 0, 0),
                                            (7, -7, 0, 0), (8, -8, 0, 0)])
    else:
        assert approx_equal(mas[0].data(), [(1, 2, 0, 0), (-1, -2, 0, 0),
                                            (3, 4, 0, 0), (-3, -4, 0, 0),
                                            (5, 6, 0, 0), (-5, -6, 0, 0),
                                            (7, 8, 0, 0), (-7, -8, 0, 0),
                                            (9, 10, 0, 0), (-9, -10, 0, 0),
                                            (11, 12, 0, 0), (-11, -12, 0, 0),
                                            (13, 14, 0, 0), (-13, -14, 0, 0),
                                            (15, 16, 0, 0), (-15, -16, 0, 0)])
    #
    columns = mtz_dataset.columns()
    columns[-1].set_type("F")
    try:
        mtz_obj.as_miller_arrays()
    except RuntimeError as e:
        if (not anomalous_flag):
            assert str(e) == 'Invalid MTZ column combination' \
              ' (incomplete Hendrickson-Lattman array),' \
              ' column labels: "HA", "HB" column types: "A", "F"'
        else:
            assert str(e) == 'Invalid MTZ column combination' \
              ' (incomplete Hendrickson-Lattman array),' \
              ' column labels: "HA(-)", "HB(-)" column types: "A", "F"'
    else:
        raise Exception_expected
def exercise_affine_occupancy_parameter():
  xs = xray.structure(
    crystal_symmetry=crystal.symmetry(unit_cell=(), space_group_symbol='hall: P 1'),
    scatterers=flex.xray_scatterer((
      xray.scatterer('C0', occupancy=1),
      xray.scatterer('C1', occupancy=1),
      xray.scatterer('C2', occupancy=1),
      xray.scatterer('C3', occupancy=1),
    )))
  sc = xs.scatterers()
  sc.flags_set_grad_occupancy(flex.size_t_range(4))

  # Two occupancies adding up to 1 (most common case of disorder)
  r = constraints.ext.reparametrisation(xs.unit_cell())
  occ_1 = r.add(constraints.independent_occupancy_parameter, sc[1])
  occ_3 = r.add(constraints.affine_asu_occupancy_parameter,
                dependee=occ_1, a=-1, b=1, scatterer=sc[3])
  r.finalise()
  r.linearise()
  assert approx_equal(occ_1.value, 1)
  assert approx_equal(occ_3.value, 0)
  jt0 = sparse.matrix(1, 2,
                     [ {0:1},   # 1st col = derivatives of occ_1
                       {0:-1},   # 2nd col = derivatives of occ_3
                     ])
  assert sparse.approx_equal(tolerance=1e-15)(r.jacobian_transpose, jt0)

  # Example illustrating the instruction SUMP in SHELX 97 manual (p. 7-26)
  # We disregard the issue of the special position which is orthogonal to the
  # point we want to test here.
  xs = xray.structure(
    crystal_symmetry=crystal.symmetry(unit_cell=(), space_group_symbol='hall: P 1'),
    scatterers=flex.xray_scatterer((
      xray.scatterer('Na+', occupancy=1),
      xray.scatterer('Ca2+', occupancy=1),
      xray.scatterer('Al3+', occupancy=0.35),
      xray.scatterer('K+', occupancy=0.15),
    )))
  sc = xs.scatterers()
  sc.flags_set_grad_occupancy(flex.size_t_range(4))

  # The constraints are:
  # fully occupied: occ(Na+) + occ(Ca2+) + occ(Al3+) + occ(K+) = 1
  # average charge +2: occ(Na+) + 2 occ(Ca2+) + 3 occ(Al3+) + occ(K+) = +2
  # This can be solved as:
  # occ(Na+)  = occ(Al3+) - occ(K+)
  # occ(Ca2+) = 1 - 2 occ(Al3+)
  r = constraints.ext.reparametrisation(xs.unit_cell())
  occ_Al = r.add(constraints.independent_occupancy_parameter, sc[2])
  occ_K  = r.add(constraints.independent_occupancy_parameter, sc[3])
  occ_Na = r.add(constraints.affine_asu_occupancy_parameter,
                 occ_Al, 1, occ_K, -1, 0, scatterer=sc[0])
  occ_Ca = r.add(constraints.affine_asu_occupancy_parameter,
                 occ_Al, -2, 1, scatterer=sc[1])
  r.finalise()
  r.linearise()
  assert approx_equal(occ_Na.value, 0.2)
  assert approx_equal(occ_Ca.value, 0.3)
  assert approx_equal(occ_Al.value, 0.35)
  assert approx_equal(occ_K.value, 0.15)
  jt0 = sparse.matrix(2, 4,
                     [
                       {0:1},         # diff occ(Al3+)
                       {1:1} ,        # diff occ(K+)
                       {0:1, 1:-1},   # diff occ(Na+)
                       {0:-2},        # diff occ(Ca2+)
                     ])
  assert sparse.approx_equal(tolerance=1e-15)(r.jacobian_transpose, jt0)
Esempio n. 13
0
def exercise_hl_ab_only(anomalous_flag):
    cs = crystal.symmetry(unit_cell=(3.95738, 5.1446, 6.72755, 83, 109, 129), space_group_symbol="P1")
    if not anomalous_flag:
        i = [(-1, 0, 1), (-1, 1, 1), (0, -1, 1), (0, 0, 1), (0, 0, 2), (0, 1, 0), (0, 1, 1), (1, -1, 0)]
    else:
        i = [
            (-1, 0, 1),
            (1, 0, -1),
            (-1, 1, 1),
            (1, -1, -1),
            (0, -1, 1),
            (0, 1, -1),
            (0, 0, 1),
            (0, 0, -1),
            (0, 0, 2),
            (0, 0, -2),
            (0, 1, 0),
            (0, -1, 0),
            (0, 1, 1),
            (0, -1, -1),
            (1, -1, 0),
            (-1, 1, 0),
        ]
    ms = miller.set(crystal_symmetry=cs, indices=flex.miller_index(i), anomalous_flag=anomalous_flag)
    ma = ms.array(data=flex.size_t_range(ms.indices().size()).as_double() + 1)
    mtz_dataset = ma.as_mtz_dataset(column_root_label="HA")
    columns = mtz_dataset.columns()
    if not anomalous_flag:
        assert columns.size() == 4
        c = columns[3]
        assert c.label() == "HA"
        c.set_type("A")
        values = c.extract_values()
        selection_valid = c.selection_valid()
        c = mtz_dataset.add_column(label="HB", type="A")
        c.set_values(values=-values, selection_valid=selection_valid)
    else:
        assert columns.size() == 5
        for i, l in [(3, "HA(+)"), (4, "HA(-)")]:
            c = columns[i]
            assert c.label() == l
            if i == 4:
                c.set_label("HB(+)")
            c.set_type("A")
        for i, l in [(3, "HA(-)"), (4, "HB(-)")]:
            c = columns[i]
            values = c.extract_values()
            selection_valid = c.selection_valid()
            c = mtz_dataset.add_column(label=l, type="A")
            c.set_values(values=-values, selection_valid=selection_valid)
    mtz_obj = mtz_dataset.mtz_object()
    mas = mtz_obj.as_miller_arrays()
    assert len(mas) == 1
    assert approx_equal(mas[0].indices(), ma.indices())
    if not anomalous_flag:
        assert approx_equal(
            mas[0].data(),
            [
                (1, -1, 0, 0),
                (2, -2, 0, 0),
                (3, -3, 0, 0),
                (4, -4, 0, 0),
                (5, -5, 0, 0),
                (6, -6, 0, 0),
                (7, -7, 0, 0),
                (8, -8, 0, 0),
            ],
        )
    else:
        assert approx_equal(
            mas[0].data(),
            [
                (1, 2, 0, 0),
                (-1, -2, 0, 0),
                (3, 4, 0, 0),
                (-3, -4, 0, 0),
                (5, 6, 0, 0),
                (-5, -6, 0, 0),
                (7, 8, 0, 0),
                (-7, -8, 0, 0),
                (9, 10, 0, 0),
                (-9, -10, 0, 0),
                (11, 12, 0, 0),
                (-11, -12, 0, 0),
                (13, 14, 0, 0),
                (-13, -14, 0, 0),
                (15, 16, 0, 0),
                (-15, -16, 0, 0),
            ],
        )
    #
    columns = mtz_dataset.columns()
    columns[-1].set_type("F")
    try:
        mtz_obj.as_miller_arrays()
    except RuntimeError, e:
        if not anomalous_flag:
            assert (
                str(e) == "Invalid MTZ column combination"
                " (incomplete Hendrickson-Lattman array),"
                ' column labels: "HA", "HB" column types: "A", "F"'
            )
        else:
            assert (
                str(e) == "Invalid MTZ column combination"
                " (incomplete Hendrickson-Lattman array),"
                ' column labels: "HA(-)", "HB(-)" column types: "A", "F"'
            )
Esempio n. 14
0
  def optimise_parameters(self, fo_sq, fc_sq,
                          scale_factor, n_independent_params):
    """ Find optimal values of a and b that give a flat analysis of the variance
        when binned by Fc/max(Fc), and a goodness of fit close to 1.

        This is done in a grid search fashion similar to Shelxl.

        self is not modified in place; instead a new instance of the weighting
        scheme is returned.

        It is intended that f_calc should already contain the contribution from
        f_mask (if a solvent mask is used).
    """
    assert fc_sq.is_xray_intensity_array()
    weighting = ext.mainstream_shelx_weighting(a=self.a, b=self.b)

    def compute_chi_sq(fo_sq, fc_sq, a,b):
      weighting.a = a
      weighting.b = b
      weights = weighting(
        fo_sq.data(), fo_sq.sigmas(), fc_sq.data(), scale_factor)
      return (flex.sum(
        weights * flex.pow2(fo_sq.data() - scale_factor * fc_sq.data())))

    fo_sq = fo_sq.deep_copy()
    fo_sq.data().set_selected(fo_sq.data() < 0, 0)

    fo2 = fo_sq.data().deep_copy()
    fo2 /= scale_factor
    sigmas = fo_sq.sigmas() / scale_factor
    sigmas_sq = flex.pow2(sigmas)
    fc2 = fc_sq.data()

    # determine starting values for a and b, formulae taken from shelxl code
    p = (fo2 + 2 * fc2)/3
    p_sq = flex.pow2(p)
    x = flex.sum((flex.pow2(fo2-fc2)-sigmas) * (p_sq/sigmas_sq))
    y = flex.sum( flex.pow2(p_sq)/sigmas_sq)
    z = flex.sum(p)
    start_a = math.sqrt(max(0.0001, 0.64*x/max(1e-8, y)))
    start_b = 0.5 * z * start_a**2 /fo_sq.size()
    a_step = 0.2 * start_a
    b_step = 0.4 * start_b

    # sort data and setup binning by fc/fc_max
    fc_sq_over_fc_sq_max = fc_sq.data()/flex.max(fc_sq.data())
    permutation = flex.sort_permutation(fc_sq_over_fc_sq_max)
    fc_sq_over_fc_sq_max = fc_sq.customized_copy(
      data=fc_sq_over_fc_sq_max).select(permutation)
    fc_sq = fc_sq.select(permutation)
    fo_sq = fo_sq.select(permutation)
    n_bins = 10
    bin_max = 0
    bin_limits = flex.size_t(1, 0)
    bin_count = flex.size_t()
    for i in range(n_bins):
      bin_limits.append(int(math.ceil((i+1) * fc_sq.size()/n_bins)))
      bin_count.append(bin_limits[i+1] - bin_limits[i])

    n = fo_sq.size()//(fo_sq.size()-n_independent_params)

    # search on a 9x9 grid to determine best values of a and b
    gridding = flex.grid(9,9)
    while (a_step > 1e-4 and b_step > 5e-3):
      tmp = flex.double(gridding, 0)
      binned_chi_sq = [tmp.deep_copy() for i in range(n_bins)]
      start_a = max(start_a, 4*a_step) - 4*a_step
      start_b = max(start_b, 4*b_step) - 4*b_step
      for i_bin in range(n_bins):
        sel = flex.size_t_range(bin_limits[i_bin], bin_limits[i_bin+1])
        fc2 = fc_sq.select(sel)
        fo2 = fo_sq.select(sel)
        b = start_b
        for j in range(9):
          a = start_a
          b += b_step
          for k in range(9):
            a += a_step
            binned_chi_sq[i_bin][j,k] += compute_chi_sq(fo2, fc2, a, b)
      min_variance = 9e9
      j_min, k_min = (0, 0)
      for j in range(9):
        for k in range(9):
          variance = 0
          for i_bin in range(n_bins):
            if bin_count[i_bin] == 0: continue
            goof = math.sqrt(binned_chi_sq[i_bin][j,k]*n/bin_count[i_bin])
            variance += (goof-1)**2
          min_variance = min(variance, min_variance)
          if variance == min_variance:
            j_min = j
            k_min = k
      start_a += k_min*a_step
      start_b += j_min*b_step
      if k_min == 8:
        a_step *= 2
        continue
      elif k_min != 0:
        a_step /= 4
      if j_min == 8:
        b_step *= 2
        continue
      elif j_min != 0:
        b_step /=4
      if start_a <= 1e-4: a_step /= 4
      if start_b <= 1e-3: b_step /= 4
    if start_a > 0.2:
      start_a = 0.2
      start_b = 0
    weighting.a = start_a
    weighting.b = start_b
    return weighting
Esempio n. 15
0
def exercise_floating_origin_dynamic_weighting(verbose=False):
  from cctbx import covariance
  import scitbx.math

  worst_condition_number_acceptable = 10

  # light elements only
  xs0 = random_structure.xray_structure(elements=['C', 'C', 'C', 'O', 'N'],
                                        use_u_aniso=True)
  fo_sq = xs0.structure_factors(d_min=0.8).f_calc().norm()
  fo_sq = fo_sq.customized_copy(sigmas=flex.double(fo_sq.size(), 1.))
  xs = xs0.deep_copy_scatterers()
  xs.shake_adp()
  xs.shake_sites_in_place(rms_difference=0.1)
  for sc in xs.scatterers():
    sc.flags.set_grad_site(True).set_grad_u_aniso(True)
  ls = least_squares.crystallographic_ls(
    fo_sq.as_xray_observations(),
    constraints.reparametrisation(
      structure=xs,
      constraints=[],
      connectivity_table=smtbx.utils.connectivity_table(xs)),
    weighting_scheme=least_squares.unit_weighting(),
    origin_fixing_restraints_type=
    origin_fixing_restraints.atomic_number_weighting)
  ls.build_up()
  lambdas = eigensystem.real_symmetric(
    ls.normal_matrix_packed_u().matrix_packed_u_as_symmetric()).values()
  # assert the restrained L.S. problem is not too ill-conditionned
  cond = math.log10(lambdas[0]/lambdas[-1])
  msg = "light elements: %.1f" % cond
  if verbose: print msg
  assert cond < worst_condition_number_acceptable, msg

  # one heavy element
  xs0 = random_structure.xray_structure(
    space_group_info=sgtbx.space_group_info('hall: P 2yb'),
    elements=['Zn', 'C', 'C', 'C', 'O', 'N'],
    use_u_aniso=True)
  fo_sq = xs0.structure_factors(d_min=0.8).f_calc().norm()
  fo_sq = fo_sq.customized_copy(sigmas=flex.double(fo_sq.size(), 1.))
  xs = xs0.deep_copy_scatterers()
  xs.shake_adp()
  xs.shake_sites_in_place(rms_difference=0.1)
  for sc in xs.scatterers():
    sc.flags.set_grad_site(True).set_grad_u_aniso(True)
  ls = least_squares.crystallographic_ls(
    fo_sq.as_xray_observations(),
    constraints.reparametrisation(
      structure=xs,
      constraints=[],
      connectivity_table=smtbx.utils.connectivity_table(xs)),
    weighting_scheme=least_squares.mainstream_shelx_weighting(),
    origin_fixing_restraints_type=
    origin_fixing_restraints.atomic_number_weighting)
  ls.build_up()
  lambdas = eigensystem.real_symmetric(
    ls.normal_matrix_packed_u().matrix_packed_u_as_symmetric()).values()
  # assert the restrained L.S. problem is not too ill-conditionned
  cond = math.log10(lambdas[0]/lambdas[-1])
  msg = "one heavy element + light elements (synthetic data): %.1f" % cond
  if verbose: print msg
  assert cond < worst_condition_number_acceptable, msg

  # are esd's for x,y,z coordinates of the same order of magnitude?
  var_cart = covariance.orthogonalize_covariance_matrix(
    ls.covariance_matrix(),
    xs.unit_cell(),
    xs.parameter_map())
  var_site_cart = covariance.extract_covariance_matrix_for_sites(
      flex.size_t_range(len(xs.scatterers())),
      var_cart,
      xs.parameter_map())
  site_esds = var_site_cart.matrix_packed_u_diagonal()
  indicators = flex.double()
  for i in xrange(0, len(site_esds), 3):
    stats = scitbx.math.basic_statistics(site_esds[i:i+3])
    indicators.append(stats.bias_corrected_standard_deviation/stats.mean)
  assert indicators.all_lt(1)

  # especially troublesome structure with one heavy element
  # (contributed by Jonathan Coome)
  xs0 = xray.structure(
    crystal_symmetry=crystal.symmetry(
      unit_cell=(8.4519, 8.4632, 18.7887, 90, 96.921, 90),
      space_group_symbol="hall: P 2yb"),
    scatterers=flex.xray_scatterer([
      xray.scatterer( #0
                      label="ZN1",
                      site=(-0.736683, -0.313978, -0.246902),
                      u=(0.000302, 0.000323, 0.000054,
                         0.000011, 0.000015, -0.000004)),
      xray.scatterer( #1
                      label="N3B",
                      site=(-0.721014, -0.313583, -0.134277),
                      u=(0.000268, 0.000237, 0.000055,
                         -0.000027, 0.000005, 0.000006)),
      xray.scatterer( #2
                      label="N3A",
                      site=(-0.733619, -0.290423, -0.357921),
                      u=(0.000229, 0.000313, 0.000053,
                         0.000022, 0.000018, -0.000018)),
      xray.scatterer( #3
                      label="C9B",
                      site=(-1.101537, -0.120157, -0.138063),
                      u=(0.000315, 0.000345, 0.000103,
                         0.000050, 0.000055, -0.000017)),
    xray.scatterer( #4
                    label="N5B",
                    site=(-0.962032, -0.220345, -0.222045),
                    u=(0.000274, 0.000392, 0.000060,
                       -0.000011, -0.000001, -0.000002)),
    xray.scatterer( #5
                    label="N1B",
                    site=(-0.498153, -0.402742, -0.208698),
                    u=(0.000252, 0.000306, 0.000063,
                       0.000000, 0.000007, 0.000018)),
    xray.scatterer( #6
                    label="C3B",
                    site=(-0.322492, -0.472610, -0.114594),
                    u=(0.000302, 0.000331, 0.000085,
                       0.000016, -0.000013, 0.000037)),
    xray.scatterer( #7
                    label="C4B",
                    site=(-0.591851, -0.368163, -0.094677),
                    u=(0.000262, 0.000255, 0.000073,
                       -0.000034, 0.000027, -0.000004)),
    xray.scatterer( #8
                    label="N4B",
                    site=(-0.969383, -0.204624, -0.150014),
                    u=(0.000279, 0.000259, 0.000070,
                       -0.000009, 0.000039, 0.000000)),
    xray.scatterer( #9
                    label="N2B",
                    site=(-0.470538, -0.414572, -0.135526),
                    u=(0.000277, 0.000282, 0.000065,
                       0.000003, 0.000021, -0.000006)),
    xray.scatterer( #10
                    label="C8A",
                    site=(-0.679889, -0.158646, -0.385629),
                    u=(0.000209, 0.000290, 0.000078,
                       0.000060, 0.000006, 0.000016)),
    xray.scatterer( #11
                    label="N5A",
                    site=(-0.649210, -0.075518, -0.263412),
                    u=(0.000307, 0.000335, 0.000057,
                       -0.000002, 0.000016, -0.000012)),
    xray.scatterer( #12
                    label="C6B",
                    site=(-0.708620, -0.325965, 0.011657),
                    u=(0.000503, 0.000318, 0.000053,
                       -0.000058, 0.000032, -0.000019)),
    xray.scatterer( #13
                    label="C10B",
                    site=(-1.179332, -0.083184, -0.202815),
                    u=(0.000280, 0.000424, 0.000136,
                       0.000094, 0.000006, 0.000013)),
    xray.scatterer( #14
                    label="N1A",
                    site=(-0.838363, -0.532191, -0.293213),
                    u=(0.000312, 0.000323, 0.000060,
                       0.000018, 0.000011, -0.000008)),
    xray.scatterer( #15
                    label="C3A",
                    site=(-0.915414, -0.671031, -0.393826),
                    u=(0.000319, 0.000384, 0.000078,
                       -0.000052, -0.000001, -0.000020)),
    xray.scatterer( #16
                    label="C1A",
                    site=(-0.907466, -0.665419, -0.276011),
                    u=(0.000371, 0.000315, 0.000079,
                       0.000006, 0.000036, 0.000033)),
    xray.scatterer( #17
                    label="C1B",
                    site=(-0.365085, -0.452753, -0.231927),
                    u=(0.000321, 0.000253, 0.000087,
                       -0.000024, 0.000047, -0.000034)),
    xray.scatterer( #18
                    label="C11A",
                    site=(-0.598622, 0.053343, -0.227354),
                    u=(0.000265, 0.000409, 0.000084,
                       0.000088, -0.000018, -0.000030)),
    xray.scatterer( #19
                    label="C2A",
                    site=(-0.958694, -0.755645, -0.337016),
                    u=(0.000394, 0.000350, 0.000106,
                       -0.000057, 0.000027, -0.000005)),
    xray.scatterer( #20
                    label="C4A",
                    site=(-0.784860, -0.407601, -0.402050),
                    u=(0.000238, 0.000296, 0.000064,
                       0.000002, 0.000011, -0.000016)),
    xray.scatterer( #21
                    label="C5A",
                    site=(-0.784185, -0.399716, -0.475491),
                    u=(0.000310, 0.000364, 0.000062,
                       0.000044, -0.000011, -0.000017)),
    xray.scatterer( #22
                    label="N4A",
                    site=(-0.630284, -0.043981, -0.333143),
                    u=(0.000290, 0.000275, 0.000074,
                       0.000021, 0.000027, 0.000013)),
    xray.scatterer( #23
                    label="C10A",
                    site=(-0.545465, 0.166922, -0.272829),
                    u=(0.000369, 0.000253, 0.000117,
                       0.000015, -0.000002, -0.000008)),
    xray.scatterer( #24
                    label="C9A",
                    site=(-0.567548, 0.102272, -0.339923),
                    u=(0.000346, 0.000335, 0.000103,
                       -0.000016, 0.000037, 0.000023)),
    xray.scatterer( #25
                    label="C11B",
                    site=(-1.089943, -0.146930, -0.253779),
                    u=(0.000262, 0.000422, 0.000102,
                       -0.000018, -0.000002, 0.000029)),
    xray.scatterer( #26
                    label="N2A",
                    site=(-0.843385, -0.537780, -0.366515),
                    u=(0.000273, 0.000309, 0.000055,
                       -0.000012, -0.000005, -0.000018)),
    xray.scatterer( #27
                    label="C7A",
                    site=(-0.674021, -0.136086, -0.457790),
                    u=(0.000362, 0.000378, 0.000074,
                       0.000043, 0.000034, 0.000016)),
    xray.scatterer( #28
                    label="C8B",
                    site=(-0.843625, -0.264182, -0.102023),
                    u=(0.000264, 0.000275, 0.000072,
                       -0.000025, 0.000019, -0.000005)),
    xray.scatterer( #29
                    label="C6A",
                    site=(-0.726731, -0.261702, -0.502366),
                    u=(0.000339, 0.000472, 0.000064,
                       0.000062, -0.000003, 0.000028)),
    xray.scatterer( #30
                    label="C5B",
                    site=(-0.577197, -0.376753, -0.020800),
                    u=(0.000349, 0.000353, 0.000066,
                       -0.000082, -0.000022, 0.000014)),
    xray.scatterer( #31
                    label="C2B",
                    site=(-0.252088, -0.497338, -0.175057),
                    u=(0.000251, 0.000342, 0.000119,
                       0.000020, 0.000034, -0.000018)),
    xray.scatterer( #32
                    label="C7B",
                    site=(-0.843956, -0.268811, -0.028080),
                    u=(0.000344, 0.000377, 0.000078,
                       -0.000029, 0.000059, -0.000007)),
    xray.scatterer( #33
                    label="F4B",
                    site=(-0.680814, -0.696808, -0.115056),
                    u=(0.000670, 0.000408, 0.000109,
                       -0.000099, 0.000139, -0.000031)),
    xray.scatterer( #34
                    label="F1B",
                    site=(-0.780326, -0.921249, -0.073962),
                    u=(0.000687, 0.000357, 0.000128,
                       -0.000152, -0.000011, 0.000021)),
    xray.scatterer( #35
                    label="B1B",
                    site=(-0.795220, -0.758128, -0.075955),
                    u=(0.000413, 0.000418, 0.000075,
                       0.000054, 0.000045, 0.000023)),
    xray.scatterer( #36
                    label="F2B",
                    site=(-0.945140, -0.714626, -0.105820),
                    u=(0.000584, 0.001371, 0.000108,
                       0.000420, 0.000067, 0.000134)),
    xray.scatterer( #37
                    label="F3B",
                    site=(-0.768914, -0.701660, -0.005161),
                    u=(0.000678, 0.000544, 0.000079,
                       -0.000000, 0.000090, -0.000021)),
    xray.scatterer( #38
                    label="F1A",
                    site=(-0.109283, -0.252334, -0.429288),
                    u=(0.000427, 0.001704, 0.000125,
                       0.000407, 0.000041, 0.000035)),
    xray.scatterer( #39
                    label="F4A",
                    site=(-0.341552, -0.262864, -0.502023),
                    u=(0.000640, 0.000557, 0.000081,
                       -0.000074, 0.000042, -0.000052)),
    xray.scatterer( #40
                    label="F3A",
                    site=(-0.324533, -0.142292, -0.393215),
                    u=(0.000471, 0.001203, 0.000134,
                       0.000333, -0.000057, -0.000220)),
    xray.scatterer( #41
                    label="F2A",
                    site=(-0.312838, -0.405405, -0.400231),
                    u=(0.002822, 0.000831, 0.000092,
                       -0.000648, 0.000115, 0.000027)),
    xray.scatterer( #42
                    label="B1A",
                    site=(-0.271589, -0.268874, -0.430724),
                    u=(0.000643, 0.000443, 0.000079,
                       0.000040, 0.000052, -0.000034)),
    xray.scatterer( #43
                    label="H5B",
                    site=(-0.475808, -0.413802, 0.004402),
                    u=0.005270),
    xray.scatterer( #44
                    label="H6B",
                    site=(-0.699519, -0.326233, 0.062781),
                    u=0.019940),
    xray.scatterer( #45
                    label="H3B",
                    site=(-0.283410, -0.484757, -0.063922),
                    u=0.029990),
    xray.scatterer( #46
                    label="H1B",
                    site=(-0.357103, -0.451819, -0.284911),
                    u=0.031070),
    xray.scatterer( #47
                    label="H10A",
                    site=(-0.495517, 0.268296, -0.256187),
                    u=0.027610),
    xray.scatterer( #48
                    label="H2B",
                    site=(-0.147129, -0.535141, -0.174699),
                    u=0.017930),
    xray.scatterer( #49
                    label="H7A",
                    site=(-0.643658, -0.031387, -0.475357),
                    u=0.020200),
    xray.scatterer( #50
                    label="H1A",
                    site=(-0.912757, -0.691043, -0.227554),
                    u=0.033320),
    xray.scatterer( #51
                    label="H7B",
                    site=(-0.933670, -0.241189, -0.010263),
                    u=0.021310),
    xray.scatterer( #52
                    label="H11B",
                    site=(-1.107736, -0.155470, -0.311996),
                    u=0.041500),
    xray.scatterer( #53
                    label="H9A",
                    site=(-0.539908, 0.139753, -0.382281),
                    u=0.007130),
    xray.scatterer( #54
                    label="H10B",
                    site=(-1.265944, -0.029610, -0.212398),
                    u=0.030910),
    xray.scatterer( #55
                    label="H3A",
                    site=(-0.934728, -0.691149, -0.450551),
                    u=0.038950),
    xray.scatterer( #56
                    label="H5A",
                    site=(-0.833654, -0.487479, -0.508239),
                    u=0.031150),
    xray.scatterer( #57
                    label="H6A",
                    site=(-0.742871, -0.242269, -0.558157),
                    u=0.050490),
    xray.scatterer( #58
                    label="H9B",
                    site=(-1.120150, -0.093752, -0.090706),
                    u=0.039310),
    xray.scatterer( #59
                    label="H11A",
                    site=(-0.593074, 0.054973, -0.180370),
                    u=0.055810),
    xray.scatterer( #60
                    label="H2A",
                    site=(-0.999576, -0.842158, -0.340837),
                    u=0.057030)
    ]))
  fo_sq = xs0.structure_factors(d_min=0.8).f_calc().norm()
  fo_sq = fo_sq.customized_copy(sigmas=flex.double(fo_sq.size(), 1.))
  for hydrogen_flag in (True, False):
    xs = xs0.deep_copy_scatterers()
    if not hydrogen_flag:
      xs.select_inplace(~xs.element_selection('H'))
    xs.shake_adp()
    xs.shake_sites_in_place(rms_difference=0.1)
    for sc in xs.scatterers():
      sc.flags.set_grad_site(True).set_grad_u_aniso(False)
    ls = least_squares.crystallographic_ls(
      fo_sq.as_xray_observations(),
      constraints.reparametrisation(
        structure=xs,
        constraints=[],
        connectivity_table=smtbx.utils.connectivity_table(xs)),
      weighting_scheme=least_squares.unit_weighting(),
      origin_fixing_restraints_type=
      origin_fixing_restraints.atomic_number_weighting)

    ls.build_up()
    lambdas = eigensystem.real_symmetric(
      ls.normal_matrix_packed_u().matrix_packed_u_as_symmetric()).values()
    # assert the restrained L.S. problem is not too ill-conditionned
    cond = math.log10(lambdas[0]/lambdas[-1])
    msg = ("one heavy element + light elements (real data) %s Hydrogens: %.1f"
           % (['without', 'with'][hydrogen_flag], cond))
    if verbose: print msg
    assert cond < worst_condition_number_acceptable, msg


    # are esd's for x,y,z coordinates of the same order of magnitude?
    var_cart = covariance.orthogonalize_covariance_matrix(
      ls.covariance_matrix(),
      xs.unit_cell(),
      xs.parameter_map())
    var_site_cart = covariance.extract_covariance_matrix_for_sites(
        flex.size_t_range(len(xs.scatterers())),
        var_cart,
        xs.parameter_map())
    site_esds = var_site_cart.matrix_packed_u_diagonal()
    indicators = flex.double()
    for i in xrange(0, len(site_esds), 3):
      stats = scitbx.math.basic_statistics(site_esds[i:i+3])
      indicators.append(stats.bias_corrected_standard_deviation/stats.mean)
    assert indicators.all_lt(1)
def exercise(verbose=0):
  distance_ideal = 1.8
  default_vdw_distance = 3.6
  vdw_1_4_factor = 3.5/3.6
  sites_cart_manual = flex.vec3_double([
    (1,3,0), (2,3,0), (3,2,0), (3,1,0), (4,1,0), (3,4,0), (4,3,0), (5,3,0),
    (6,2,0), (7,2,0), (8,3,0), (7,4,0), (6,4,0), (7,5,0), (6,6,0), (8,6,0)])
  bond_proxies = geometry_restraints.bond_sorted_asu_proxies(asu_mappings=None)
  for i_seqs in [(0,1),(1,2),(2,3),(3,4),(1,5),(2,6),(5,6),
                 (6,7),(7,8),(8,9),(9,10),(10,11),(11,12),
                 (12,7),(11,13),(13,14),(14,15),(15,13)]:
    bond_proxies.process(geometry_restraints.bond_simple_proxy(
      i_seqs=i_seqs, distance_ideal=distance_ideal, weight=100))
  angle_proxies = geometry_restraints.shared_angle_proxy()
  for i_seqs,angle_ideal in [[(0,1,2),135],
                             [(0,1,5),135],
                             [(1,2,3),135],
                             [(3,2,6),135],
                             [(2,3,4),120],
                             [(1,2,6),90],
                             [(2,6,5),90],
                             [(6,5,1),90],
                             [(5,1,2),90],
                             [(2,6,7),135],
                             [(5,6,7),135],
                             [(6,7,8),120],
                             [(6,7,12),120],
                             [(7,8,9),120],
                             [(8,9,10),120],
                             [(9,10,11),120],
                             [(10,11,12),120],
                             [(11,12,7),120],
                             [(12,7,8),120],
                             [(10,11,13),120],
                             [(12,11,13),120],
                             [(11,13,15),150],
                             [(11,13,14),150],
                             [(13,15,14),60],
                             [(15,14,13),60],
                             [(14,13,15),60]]:
    angle_proxies.append(geometry_restraints.angle_proxy(
      i_seqs=i_seqs, angle_ideal=angle_ideal, weight=1))
  if (0 or verbose):
    dump_pdb(file_name="manual.pdb", sites_cart=sites_cart_manual)
  for traditional_convergence_test in [True,False]:
    for sites_cart_selection in [True, False]:
      sites_cart = sites_cart_manual.deep_copy()
      if sites_cart_selection:
        sites_cart_selection = flex.bool(sites_cart.size(), True)
        sites_cart_selection[1] = False
      assert bond_proxies.asu.size() == 0
      bond_params_table = geometry_restraints.extract_bond_params(
        n_seq=sites_cart.size(),
        bond_simple_proxies=bond_proxies.simple)
      manager = geometry_restraints.manager.manager(
        bond_params_table=bond_params_table,
        angle_proxies=angle_proxies)
      minimized = geometry_restraints.lbfgs.lbfgs(
        sites_cart=sites_cart,
        geometry_restraints_manager=manager,
        lbfgs_termination_params=scitbx.lbfgs.termination_parameters(
          traditional_convergence_test=traditional_convergence_test,
          drop_convergence_test_max_drop_eps=1.e-20,
          drop_convergence_test_iteration_coefficient=1,
          max_iterations=1000),
        sites_cart_selection=sites_cart_selection,
        )
      assert minimized.minimizer.iter() > 100
      sites_cart_minimized_1 = sites_cart.deep_copy()
      if (0 or verbose):
        dump_pdb(
          file_name="minimized_1.pdb", sites_cart=sites_cart_minimized_1)
      bond_deltas = geometry_restraints.bond_deltas(
        sites_cart=sites_cart_minimized_1,
        proxies=bond_proxies.simple)
      angle_deltas = geometry_restraints.angle_deltas(
        sites_cart=sites_cart_minimized_1,
        proxies=angle_proxies)
      if (0 or verbose):
        for proxy,delta in zip(bond_proxies.simple, bond_deltas):
          print "bond:", proxy.i_seqs, delta
        for proxy,delta in zip(angle_proxies, angle_deltas):
          print "angle:", proxy.i_seqs, delta
      assert is_below_limit(
        value=flex.max(flex.abs(bond_deltas)), limit=0, eps=1.e-6)
      assert is_below_limit(
        value=flex.max(flex.abs(angle_deltas)), limit=0, eps=2.e-6)
  sites_cart += matrix.col((1,1,0)) - matrix.col(sites_cart.min())
  unit_cell_lengths = list(  matrix.col(sites_cart.max())
                           + matrix.col((1,-1.2,4)))
  unit_cell_lengths[1] *= 2
  unit_cell_lengths[2] *= 2
  xray_structure = xray.structure(
    crystal_symmetry=crystal.symmetry(
      unit_cell=unit_cell_lengths,
      space_group_symbol="P112"))
  for serial,site in zip(count(1), sites_cart):
    xray_structure.add_scatterer(xray.scatterer(
      label="C%02d"%serial,
      site=xray_structure.unit_cell().fractionalize(site)))
  if (0 or verbose):
    xray_structure.show_summary().show_scatterers()
  p1_structure = (xray_structure
    .apply_shift((-.5,-.5,0))
    .expand_to_p1()
    .apply_shift((.5,.5,0)))
  for shift in [(1,0,0), (0,1,0), (0,0,1)]:
    p1_structure.add_scatterers(p1_structure.apply_shift(shift).scatterers())
  if (0 or verbose):
    open("p1_structure.pdb", "w").write(p1_structure.as_pdb_file())
  nonbonded_cutoff = 6.5
  asu_mappings = xray_structure.asu_mappings(
    buffer_thickness=nonbonded_cutoff)
  bond_asu_table = crystal.pair_asu_table(asu_mappings=asu_mappings)
  geometry_restraints.add_pairs(bond_asu_table, bond_proxies.simple)
  shell_asu_tables = crystal.coordination_sequences.shell_asu_tables(
    pair_asu_table=bond_asu_table,
    max_shell=3)
  shell_sym_tables = [shell_asu_table.extract_pair_sym_table()
    for shell_asu_table in shell_asu_tables]
  bond_params_table = geometry_restraints.extract_bond_params(
    n_seq=sites_cart.size(),
    bond_simple_proxies=bond_proxies.simple)
  atom_energy_types = flex.std_string(sites_cart.size(), "Default")
  nonbonded_params = geometry_restraints.nonbonded_params(
    factor_1_4_interactions=vdw_1_4_factor,
    const_shrink_1_4_interactions=0,
    default_distance=default_vdw_distance)
  nonbonded_params.distance_table.setdefault(
    "Default")["Default"] = default_vdw_distance
  pair_proxies = geometry_restraints.pair_proxies(
    bond_params_table=bond_params_table,
    shell_asu_tables=shell_asu_tables,
    model_indices=None,
    conformer_indices=None,
    nonbonded_params=nonbonded_params,
    nonbonded_types=atom_energy_types,
    nonbonded_distance_cutoff_plus_buffer=nonbonded_cutoff)
  if (0 or verbose):
    print "pair_proxies.bond_proxies.n_total():", \
           pair_proxies.bond_proxies.n_total(),
    print "simple:", pair_proxies.bond_proxies.simple.size(),
    print "sym:", pair_proxies.bond_proxies.asu.size()
    print "pair_proxies.nonbonded_proxies.n_total():", \
           pair_proxies.nonbonded_proxies.n_total(),
    print "simple:", pair_proxies.nonbonded_proxies.simple.size(),
    print "sym:", pair_proxies.nonbonded_proxies.asu.size()
    print "min_distance_nonbonded: %.2f" % flex.min(
      geometry_restraints.nonbonded_deltas(
        sites_cart=sites_cart,
        sorted_asu_proxies=pair_proxies.nonbonded_proxies))
  s = StringIO()
  pair_proxies.bond_proxies.show_histogram_of_model_distances(
    sites_cart=sites_cart,
    f=s,
    prefix="[]")
  assert s.getvalue().splitlines()[0] == "[]Histogram of bond lengths:"
  assert s.getvalue().splitlines()[5].startswith("[]      1.80 -     1.80:")
  s = StringIO()
  pair_proxies.bond_proxies.show_histogram_of_deltas(
    sites_cart=sites_cart,
    f=s,
    prefix="][")
  assert s.getvalue().splitlines()[0] == "][Histogram of bond deltas:"
  assert s.getvalue().splitlines()[5].startswith("][     0.000 -    0.000:")
  s = StringIO()
  pair_proxies.bond_proxies.show_sorted(
    by_value="residual",
    sites_cart=sites_cart,
    max_items=3,
    f=s,
    prefix=":;")
  l = s.getvalue().splitlines()
  assert l[0] == ":;Bond restraints: 18"
  assert l[1] == ":;Sorted by residual:"
  assert l[2].startswith(":;bond ")
  assert l[3].startswith(":;     ")
  assert l[4] == ":;  ideal  model  delta    sigma   weight residual"
  for i in [5,-2]:
    assert l[i].startswith(":;  1.800  1.800 ")
  assert l[-1] == ":;... (remaining 15 not shown)"
  s = StringIO()
  pair_proxies.nonbonded_proxies.show_histogram_of_model_distances(
    sites_cart=sites_cart,
    f=s,
    prefix="]^")
  assert not show_diff(s.getvalue(), """\
]^Histogram of nonbonded interaction distances:
]^      2.16 -     3.03: 3
]^      3.03 -     3.89: 12
]^      3.89 -     4.75: 28
]^      4.75 -     5.61: 44
]^      5.61 -     6.48: 54
""")
  s = StringIO()
  pair_proxies.nonbonded_proxies.show_sorted(
    by_value="delta",
    sites_cart=sites_cart,
    max_items=7,
    f=s,
    prefix=">,")
  assert not show_diff(s.getvalue(), """\
>,Nonbonded interactions: 141
>,Sorted by model distance:
>,nonbonded 15
>,          15
>,   model   vdw sym.op.
>,   2.164 3.600 -x+2,-y+1,z
...
>,nonbonded 4
>,          8
>,   model   vdw
>,   3.414 3.600
>,... (remaining 134 not shown)
""",
    selections=[range(6), range(-5,0)])
  vdw_1_sticks = []
  vdw_2_sticks = []
  for proxy in pair_proxies.nonbonded_proxies.simple:
    if (proxy.vdw_distance == default_vdw_distance):
      vdw_1_sticks.append(pml_stick(
        begin=sites_cart[proxy.i_seqs[0]],
        end=sites_cart[proxy.i_seqs[1]]))
    else:
      vdw_2_sticks.append(pml_stick(
        begin=sites_cart[proxy.i_seqs[0]],
        end=sites_cart[proxy.i_seqs[1]]))
  mps = asu_mappings.mappings()
  for proxy in pair_proxies.nonbonded_proxies.asu:
    if (proxy.vdw_distance == default_vdw_distance):
      vdw_1_sticks.append(pml_stick(
        begin=mps[proxy.i_seq][0].mapped_site(),
        end=mps[proxy.j_seq][proxy.j_sym].mapped_site()))
    else:
      vdw_2_sticks.append(pml_stick(
        begin=mps[proxy.i_seq][0].mapped_site(),
        end=mps[proxy.j_seq][proxy.j_sym].mapped_site()))
  if (0 or verbose):
    pml_write(f=open("vdw_1.pml", "w"), label="vdw_1", sticks=vdw_1_sticks)
    pml_write(f=open("vdw_2.pml", "w"), label="vdw_2", sticks=vdw_2_sticks)
  #
  i_pdb = count(2)
  for use_crystal_symmetry in [False, True]:
    if (not use_crystal_symmetry):
      crystal_symmetry = None
      site_symmetry_table = None
    else:
      crystal_symmetry = xray_structure
      site_symmetry_table = xray_structure.site_symmetry_table()
    for sites_cart in [sites_cart_manual.deep_copy(),
                       sites_cart_minimized_1.deep_copy()]:
      manager = geometry_restraints.manager.manager(
        crystal_symmetry=crystal_symmetry,
        site_symmetry_table=site_symmetry_table,
        nonbonded_params=nonbonded_params,
        nonbonded_types=atom_energy_types,
        nonbonded_function=geometry_restraints.prolsq_repulsion_function(),
        bond_params_table=bond_params_table,
        shell_sym_tables=shell_sym_tables,
        nonbonded_distance_cutoff=nonbonded_cutoff,
        nonbonded_buffer=1,
        angle_proxies=angle_proxies,
        plain_pairs_radius=5)
      manager = manager.select(selection=flex.bool(sites_cart.size(), True))
      manager = manager.select(
        iselection=flex.size_t_range(stop=sites_cart.size()))
      pair_proxies = manager.pair_proxies(sites_cart=sites_cart)
      minimized = geometry_restraints.lbfgs.lbfgs(
        sites_cart=sites_cart,
        geometry_restraints_manager=manager,
        lbfgs_termination_params=scitbx.lbfgs.termination_parameters(
          max_iterations=1000))
      if (0 or verbose):
        minimized.final_target_result.show()
        print "number of function evaluations:", minimized.minimizer.nfun()
        print "n_updates_pair_proxies:", manager.n_updates_pair_proxies
      if (not use_crystal_symmetry):
        assert minimized.final_target_result.bond_residual_sum < 1.e-3
        assert minimized.final_target_result.nonbonded_residual_sum < 0.1
      else:
        assert minimized.final_target_result.bond_residual_sum < 1.e-2
        assert minimized.final_target_result.nonbonded_residual_sum < 0.1
      assert minimized.final_target_result.angle_residual_sum < 1.e-3
      if (0 or verbose):
        pdb_file_name = "minimized_%d.pdb" % i_pdb.next()
        print "Writing file:", pdb_file_name
        dump_pdb(file_name=pdb_file_name, sites_cart=sites_cart)
      if (manager.site_symmetry_table is None):
        additional_site_symmetry_table = None
      else:
        additional_site_symmetry_table = sgtbx.site_symmetry_table()
      assert manager.new_including_isolated_sites(
        n_additional_sites=0,
        site_symmetry_table=additional_site_symmetry_table,
        nonbonded_types=flex.std_string()).plain_pairs_radius \
          == manager.plain_pairs_radius
      if (crystal_symmetry is not None):
        assert len(manager.plain_pair_sym_table) == 16
        if (0 or verbose):
          manager.plain_pair_sym_table.show()
  #
  xray_structure.set_u_iso(values=flex.double([
    0.77599982480241358, 0.38745781137212021, 0.20667558236418682,
    0.99759840171302094, 0.8917287406687805, 0.64780251325379845,
    0.24878590382983534, 0.59480621182194615, 0.58695637792905142,
    0.33997130213653637, 0.51258699130743735, 0.79760289141276675,
    0.39996577657875021, 0.4329328819341467, 0.70422156561726479,
    0.87260110626999332]))
  class parameters: pass
  parameters.sphere_radius = 5
  parameters.distance_power = 0.7
  parameters.average_power = 0.9
  parameters.wilson_b_weight = 1.3952
  parameters.wilson_b_weight_auto = False
  adp_energies = adp_restraints.energies_iso(
    geometry_restraints_manager=manager,
    xray_structure=xray_structure,
    parameters=parameters,
    wilson_b=None,
    use_hd=False,
    use_u_local_only = False,
    compute_gradients=False,
    gradients=None,
    normalization=False,
    collect=True)
  assert adp_energies.number_of_restraints == 69
  assert approx_equal(adp_energies.residual_sum, 6.24865382467)
  assert adp_energies.gradients is None
  assert adp_energies.u_i.size() == adp_energies.number_of_restraints
  assert adp_energies.u_j.size() == adp_energies.number_of_restraints
  assert adp_energies.r_ij.size() == adp_energies.number_of_restraints
  for wilson_b in [None, 10, 100]:
    finite_difference_gradients = flex.double()
    eps = 1.e-6
    for i_scatterer in xrange(xray_structure.scatterers().size()):
      rs = []
      for signed_eps in [eps, -eps]:
        xray_structure_eps = xray_structure.deep_copy_scatterers()
        xray_structure_eps.scatterers()[i_scatterer].u_iso += signed_eps
        adp_energies = adp_restraints.energies_iso(
          geometry_restraints_manager=manager,
          xray_structure=xray_structure_eps,
          parameters=parameters,
          wilson_b=wilson_b,
          use_u_local_only = False,
          use_hd=False,
          compute_gradients=True,
          gradients=None,
          normalization=False,
          collect=False)
        rs.append(adp_energies.residual_sum)
        assert adp_energies.gradients.size() \
            == xray_structure.scatterers().size()
        assert adp_energies.u_i == None
        assert adp_energies.u_j == None
        assert adp_energies.r_ij == None
      finite_difference_gradients.append((rs[0]-rs[1])/(2*eps))
    sel = flex.bool(xray_structure.scatterers().size(), True)
    xray_structure.scatterers().flags_set_grad_u_iso(sel.iselection())
    adp_energies = adp_restraints.energies_iso(
      geometry_restraints_manager=manager,
      xray_structure=xray_structure,
      parameters=parameters,
      wilson_b=wilson_b,
      use_u_local_only = False,
      use_hd=False,
      compute_gradients=True,
      gradients=None,
      normalization=False,
      collect=False)
    assert approx_equal(adp_energies.gradients, finite_difference_gradients)
  print "OK"