예제 #1
0
    def create_models(self):
        # build models, with a larger crystal than default in order to get plenty of
        # reflections on the 'still' image
        overrides = """
    geometry.parameters.crystal.a.length.range=40 50;
    geometry.parameters.crystal.b.length.range=40 50;
    geometry.parameters.crystal.c.length.range=40 50;
    geometry.parameters.random_seed = 42"""

        master_phil = parse("""
        include scope dials.test.algorithms.refinement.geometry_phil
        """,
                            process_includes=True)

        models = Extract(master_phil, overrides)

        # keep track of the models
        self.detector = models.detector
        self.gonio = models.goniometer
        self.crystal = models.crystal
        self.beam = models.beam

        # Create a stills ExperimentList
        self.stills_experiments = ExperimentList()
        self.stills_experiments.append(
            Experiment(beam=self.beam,
                       detector=self.detector,
                       crystal=self.crystal,
                       imageset=None))

        # keep track of the parameterisation of the models
        self.det_param = DetectorParameterisationSinglePanel(self.detector)
        self.s0_param = BeamParameterisation(self.beam, self.gonio)
        self.xlo_param = CrystalOrientationParameterisation(self.crystal)
        self.xluc_param = CrystalUnitCellParameterisation(self.crystal)
예제 #2
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    def create_models(self, cmdline_overrides=None):
        from dxtbx.model import ScanFactory
        from libtbx.phil import parse

        from dials.test.algorithms.refinement.setup_geometry import Extract

        if cmdline_overrides is None:
            cmdline_overrides = []
        overrides = """geometry.parameters.crystal.a.length.range = 10 50
geometry.parameters.crystal.b.length.range = 10 50
geometry.parameters.crystal.c.length.range = 10 50"""

        master_phil = parse(
            """
    include scope dials.test.algorithms.refinement.geometry_phil
    """,
            process_includes=True,
        )

        # Extract models
        models = Extract(master_phil,
                         overrides,
                         cmdline_args=cmdline_overrides)
        self.detector = models.detector
        self.goniometer = models.goniometer
        self.crystal = models.crystal
        self.beam = models.beam

        # Make a scan of 1-20 * 0.5 deg images
        sf = ScanFactory()
        self.scan = sf.make_scan((1, 20), 0.5, (0, 0.5), list(range(20)))

        # Generate an ExperimentList
        self.experiments = ExperimentList()
        self.experiments.append(
            Experiment(
                beam=self.beam,
                detector=self.detector,
                goniometer=self.goniometer,
                scan=self.scan,
                crystal=self.crystal,
                imageset=None,
            ))

        # Create a reflection predictor for the experiments
        self.ref_predictor = ScansExperimentsPredictor(self.experiments)

        # Create scan-varying parameterisations of these models, with 3 samples
        self.det_param = ScanVaryingDetectorParameterisationSinglePanel(
            self.detector, self.scan.get_array_range(), 3)
        self.s0_param = ScanVaryingBeamParameterisation(
            self.beam, self.scan.get_array_range(), 3, self.goniometer)
        self.xlo_param = ScanVaryingCrystalOrientationParameterisation(
            self.crystal, self.scan.get_array_range(), 3)
        self.xluc_param = ScanVaryingCrystalUnitCellParameterisation(
            self.crystal, self.scan.get_array_range(), 3)
        self.gon_param = ScanVaryingGoniometerParameterisation(
            self.goniometer, self.scan.get_array_range(), 3, self.beam)
예제 #3
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def create_experiments(image_start=1):

    # Create models
    from libtbx.phil import parse

    overrides = """geometry.parameters.crystal.a.length.range = 10 50
  geometry.parameters.crystal.b.length.range = 10 50
  geometry.parameters.crystal.c.length.range = 10 50"""
    master_phil = parse(
        """
      include scope dials.test.algorithms.refinement.geometry_phil
      """,
        process_includes=True,
    )
    from dials.test.algorithms.refinement.setup_geometry import Extract

    models = Extract(master_phil, overrides)

    detector = models.detector
    goniometer = models.goniometer
    crystal = models.crystal
    beam = models.beam

    # Build a mock scan for a 72 degree sequence
    from dxtbx.model import ScanFactory

    sf = ScanFactory()
    scan = sf.make_scan(
        image_range=(image_start, image_start + 720 - 1),
        exposure_times=0.1,
        oscillation=(0, 0.1),
        epochs=list(range(720)),
        deg=True,
    )

    # No matter what image_start is, scan should start at 0.0 and end at 72.0 deg
    assert scan.get_oscillation_range(deg=True) == (0.0, 72.0)

    # Create an ExperimentList
    experiments = ExperimentList()
    experiments.append(
        Experiment(
            beam=beam,
            detector=detector,
            goniometer=goniometer,
            scan=scan,
            crystal=crystal,
            imageset=None,
        )
    )

    return experiments
def test():
    from cctbx.sgtbx import space_group, space_group_symbols

    # We will set up a mock scan
    from dxtbx.model import ScanFactory
    from dxtbx.model.experiment_list import Experiment, ExperimentList
    from libtbx.phil import parse
    from scitbx import matrix
    from scitbx.array_family import flex

    from dials.algorithms.refinement.prediction.managed_predictors import (
        ScansExperimentsPredictor,
        ScansRayPredictor,
    )

    # Reflection prediction
    from dials.algorithms.spot_prediction import IndexGenerator

    # Building experimental models
    from dials.test.algorithms.refinement.setup_geometry import Extract

    master_phil = parse(
        """
  include scope dials.test.algorithms.refinement.geometry_phil
  include scope dials.test.algorithms.refinement.minimiser_phil
  """,
        process_includes=True,
    )

    overrides = """geometry.parameters.crystal.a.length.range = 10 50
  geometry.parameters.crystal.b.length.range = 10 50
  geometry.parameters.crystal.c.length.range = 10 50"""

    models = Extract(master_phil, local_overrides=overrides)

    mydetector = models.detector
    mygonio = models.goniometer
    mycrystal = models.crystal
    mybeam = models.beam

    #############################
    # Generate some reflections #
    #############################

    # All indices in a 2.0 Angstrom sphere
    resolution = 2.0
    index_generator = IndexGenerator(
        mycrystal.get_unit_cell(),
        space_group(space_group_symbols(1).hall()).type(),
        resolution,
    )
    indices = index_generator.to_array()

    # Build a mock scan for a 30 degree sequence
    sf = ScanFactory()
    myscan = sf.make_scan(
        image_range=(1, 300),
        exposure_times=0.1,
        oscillation=(0, 0.1),
        epochs=list(range(300)),
        deg=True,
    )
    sequence_range = myscan.get_oscillation_range(deg=False)
    assert sequence_range == pytest.approx((0.0, math.pi / 6.0))
    im_width = myscan.get_oscillation(deg=False)[1]
    assert im_width == pytest.approx(0.1 * math.pi / 180.0)

    # Create an ExperimentList for ScansRayPredictor
    experiments = ExperimentList()
    experiments.append(
        Experiment(
            beam=mybeam,
            detector=mydetector,
            goniometer=mygonio,
            scan=myscan,
            crystal=mycrystal,
            imageset=None,
        ))

    # Select those that are excited in a 30 degree sequence and get angles
    ray_predictor = ScansRayPredictor(experiments, sequence_range)
    obs_refs = ray_predictor(indices)

    # Set the experiment number
    obs_refs["id"] = flex.int(len(obs_refs), 0)

    # Calculate intersections
    ref_predictor = ScansExperimentsPredictor(experiments)
    obs_refs = ref_predictor(obs_refs)

    print("Total number of observations made", len(obs_refs))

    s0 = matrix.col(mybeam.get_s0())
    spindle = matrix.col(mygonio.get_rotation_axis())

    for ref in obs_refs.rows():
        # get the s1 vector of this reflection
        s1 = matrix.col(ref["s1"])

        r = s1 - s0
        r_orig = r.rotate_around_origin(spindle, -1.0, deg=True)

        # is it outside the Ewald sphere (i.e. entering)?
        test = (s0 + r_orig).length() > s0.length()
        assert ref["entering"] == test
예제 #5
0
def test_fd_derivatives():
    """Test derivatives of the prediction equation"""

    from libtbx.phil import parse

    # Import model builder
    from dials.test.algorithms.refinement.setup_geometry import Extract

    # Create models
    overrides = """geometry.parameters.crystal.a.length.range = 10 50
  geometry.parameters.crystal.b.length.range = 10 50
  geometry.parameters.crystal.c.length.range = 10 50"""
    master_phil = parse(
        """
      include scope dials.test.algorithms.refinement.geometry_phil
      """,
        process_includes=True,
    )
    models = Extract(master_phil, overrides)

    mydetector = models.detector
    mygonio = models.goniometer
    mycrystal = models.crystal
    mybeam = models.beam

    # Build a mock scan for a 72 degree sequence
    from dxtbx.model import ScanFactory

    sf = ScanFactory()
    myscan = sf.make_scan(
        image_range=(1, 720),
        exposure_times=0.1,
        oscillation=(0, 0.1),
        epochs=list(range(720)),
        deg=True,
    )

    # Create a parameterisation of the crystal unit cell
    from dials.algorithms.refinement.parameterisation.crystal_parameters import (
        CrystalUnitCellParameterisation, )

    xluc_param = CrystalUnitCellParameterisation(mycrystal)

    # Create an ExperimentList
    experiments = ExperimentList()
    experiments.append(
        Experiment(
            beam=mybeam,
            detector=mydetector,
            goniometer=mygonio,
            scan=myscan,
            crystal=mycrystal,
            imageset=None,
        ))

    # Build a prediction parameterisation for two theta prediction
    pred_param = TwoThetaPredictionParameterisation(
        experiments,
        detector_parameterisations=None,
        beam_parameterisations=None,
        xl_orientation_parameterisations=None,
        xl_unit_cell_parameterisations=[xluc_param],
    )

    # Generate some reflections
    obs_refs, ref_predictor = generate_reflections(experiments)

    # Build a ReflectionManager with overloads for handling 2theta residuals
    refman = TwoThetaReflectionManager(obs_refs,
                                       experiments,
                                       outlier_detector=None)

    # Build a TwoThetaExperimentsPredictor
    ref_predictor = TwoThetaExperimentsPredictor(experiments)

    # Make a target for the least squares 2theta residual
    target = TwoThetaTarget(experiments, ref_predictor, refman, pred_param)

    # Keep only reflections that pass inclusion criteria and have predictions
    reflections = refman.get_matches()

    # Get analytical gradients
    an_grads = pred_param.get_gradients(reflections)

    # Get finite difference gradients
    p_vals = pred_param.get_param_vals()
    deltas = [1.0e-7] * len(p_vals)

    for i in range(len(deltas)):

        val = p_vals[i]

        p_vals[i] -= deltas[i] / 2.0
        pred_param.set_param_vals(p_vals)

        target.predict()
        reflections = refman.get_matches()

        rev_state = reflections["2theta_resid"].deep_copy()

        p_vals[i] += deltas[i]
        pred_param.set_param_vals(p_vals)

        target.predict()
        reflections = refman.get_matches()

        fwd_state = reflections["2theta_resid"].deep_copy()
        p_vals[i] = val

        fd = fwd_state - rev_state
        fd /= deltas[i]

        # compare with analytical calculation
        assert approx_equal(fd, an_grads[i]["d2theta_dp"], eps=1.0e-6)

    # return to the initial state
    pred_param.set_param_vals(p_vals)
def test():
    # Build models, with a larger crystal than default in order to get plenty of
    # reflections on the 'still' image
    overrides = """
  geometry.parameters.crystal.a.length.range=40 50;
  geometry.parameters.crystal.b.length.range=40 50;
  geometry.parameters.crystal.c.length.range=40 50;
  geometry.parameters.random_seed = 42"""

    master_phil = parse(
        """
      include scope dials.test.algorithms.refinement.geometry_phil
      """,
        process_includes=True,
    )

    models = Extract(master_phil, overrides)

    mydetector = models.detector
    mygonio = models.goniometer
    mycrystal = models.crystal
    mybeam = models.beam

    # Build a mock scan for a 3 degree sweep
    from dxtbx.model import ScanFactory

    sf = ScanFactory()
    myscan = sf.make_scan(
        image_range=(1, 1),
        exposure_times=0.1,
        oscillation=(0, 3.0),
        epochs=list(range(1)),
        deg=True,
    )
    sweep_range = myscan.get_oscillation_range(deg=False)

    # Create parameterisations of these models
    det_param = DetectorParameterisationSinglePanel(mydetector)
    s0_param = BeamParameterisation(mybeam, mygonio)
    xlo_param = CrystalOrientationParameterisation(mycrystal)
    xluc_param = CrystalUnitCellParameterisation(mycrystal)

    # Create a scans ExperimentList, only for generating reflections
    experiments = ExperimentList()
    experiments.append(
        Experiment(
            beam=mybeam,
            detector=mydetector,
            goniometer=mygonio,
            scan=myscan,
            crystal=mycrystal,
            imageset=None,
        ))

    # Create a stills ExperimentList
    stills_experiments = ExperimentList()
    stills_experiments.append(
        Experiment(beam=mybeam,
                   detector=mydetector,
                   crystal=mycrystal,
                   imageset=None))

    # Generate rays - only to work out which hkls are predicted
    ray_predictor = ScansRayPredictor(experiments, sweep_range)
    resolution = 2.0
    index_generator = IndexGenerator(
        mycrystal.get_unit_cell(),
        space_group(space_group_symbols(1).hall()).type(),
        resolution,
    )
    indices = index_generator.to_array()
    rays = ray_predictor(indices)

    # Make a standard reflection_table and copy in the ray data
    reflections = flex.reflection_table.empty_standard(len(rays))
    reflections.update(rays)

    # Build a standard prediction parameterisation for the stills experiment to do
    # FD calculation (not used for its analytical gradients)
    pred_param = StillsPredictionParameterisation(
        stills_experiments,
        detector_parameterisations=[det_param],
        beam_parameterisations=[s0_param],
        xl_orientation_parameterisations=[xlo_param],
        xl_unit_cell_parameterisations=[xluc_param],
    )

    # Make a managed SphericalRelpStillsReflectionPredictor reflection predictor
    # for the first (only) experiment
    ref_predictor = Predictor(stills_experiments)

    # Predict these reflections in place. Must do this ahead of calculating
    # the analytical gradients so quantities like s1 are correct
    ref_predictor.update()
    ref_predictor.predict(reflections)

    # calculate analytical gradients
    ag = AnalyticalGradients(
        stills_experiments,
        detector_parameterisation=det_param,
        beam_parameterisation=s0_param,
        xl_orientation_parameterisation=xlo_param,
        xl_unit_cell_parameterisation=xluc_param,
    )
    an_grads = ag.get_beam_gradients(reflections)
    an_grads.update(ag.get_crystal_orientation_gradients(reflections))
    an_grads.update(ag.get_crystal_unit_cell_gradients(reflections))

    # get finite difference gradients
    p_vals = pred_param.get_param_vals()
    deltas = [1.0e-7] * len(p_vals)

    fd_grads = []
    p_names = pred_param.get_param_names()
    for i, delta in enumerate(deltas):

        # save parameter value
        val = p_vals[i]

        # calc reverse state
        p_vals[i] -= delta / 2.0
        pred_param.set_param_vals(p_vals)

        ref_predictor.update()
        ref_predictor.predict(reflections)

        x, y, _ = reflections["xyzcal.mm"].deep_copy().parts()
        s1 = reflections["s1"].deep_copy()
        rev_state = s1

        # calc forward state
        p_vals[i] += delta
        pred_param.set_param_vals(p_vals)

        ref_predictor.update()
        ref_predictor.predict(reflections)

        x, y, _ = reflections["xyzcal.mm"].deep_copy().parts()
        s1 = reflections["s1"].deep_copy()
        fwd_state = s1

        # reset parameter to saved value
        p_vals[i] = val

        # finite difference - currently for s1 only
        fd = fwd_state - rev_state
        inv_delta = 1.0 / delta
        s1_grads = fd * inv_delta

        # store gradients
        fd_grads.append({"name": p_names[i], "ds1": s1_grads})

    # return to the initial state
    pred_param.set_param_vals(p_vals)

    for i, fd_grad in enumerate(fd_grads):

        ## compare FD with analytical calculations
        print("\n\nParameter {0}: {1}".format(i, fd_grad["name"]))

        print("d[s1]/dp for the first reflection")
        print("finite diff", fd_grad["ds1"][0])
        try:
            an_grad = an_grads[fd_grad["name"]]
        except KeyError:
            continue

        print("checking analytical vs finite difference gradients for s1")
        for a, b in zip(fd_grad["ds1"], an_grad["ds1"]):
            assert a == pytest.approx(b, abs=1e-7)
def test_single_crystal_restraints_gradients():
    """Simple test with a single triclinic crystal restrained to a target unit cell"""

    from dxtbx.model.experiment_list import Experiment, ExperimentList

    from dials.algorithms.refinement.parameterisation.beam_parameters import (
        BeamParameterisation, )
    from dials.algorithms.refinement.parameterisation.crystal_parameters import (
        CrystalOrientationParameterisation,
        CrystalUnitCellParameterisation,
    )
    from dials.algorithms.refinement.parameterisation.detector_parameters import (
        DetectorParameterisationSinglePanel, )
    from dials.algorithms.refinement.parameterisation.prediction_parameters import (
        XYPhiPredictionParameterisation, )
    from dials.test.algorithms.refinement.setup_geometry import Extract

    overrides = """geometry.parameters.crystal.a.length.range = 10 50
  geometry.parameters.crystal.b.length.range = 10 50
  geometry.parameters.crystal.c.length.range = 10 50"""

    master_phil = parse(
        """
      include scope dials.test.algorithms.refinement.geometry_phil
      """,
        process_includes=True,
    )

    models = Extract(master_phil, overrides)

    mydetector = models.detector
    mygonio = models.goniometer
    mycrystal = models.crystal
    mybeam = models.beam

    # Build a mock scan for a 72 degree sequence
    from dxtbx.model import ScanFactory

    sf = ScanFactory()
    myscan = sf.make_scan(
        image_range=(1, 720),
        exposure_times=0.1,
        oscillation=(0, 0.1),
        epochs=list(range(720)),
        deg=True,
    )

    # Create parameterisations of these models
    det_param = DetectorParameterisationSinglePanel(mydetector)
    s0_param = BeamParameterisation(mybeam, mygonio)
    xlo_param = CrystalOrientationParameterisation(mycrystal)
    xluc_param = CrystalUnitCellParameterisation(mycrystal)

    # Create an ExperimentList
    experiments = ExperimentList()
    experiments.append(
        Experiment(
            beam=mybeam,
            detector=mydetector,
            goniometer=mygonio,
            scan=myscan,
            crystal=mycrystal,
            imageset=None,
        ))

    # Build a prediction parameterisation
    pred_param = XYPhiPredictionParameterisation(
        experiments,
        detector_parameterisations=[det_param],
        beam_parameterisations=[s0_param],
        xl_orientation_parameterisations=[xlo_param],
        xl_unit_cell_parameterisations=[xluc_param],
    )

    # Build a restraints parameterisation
    rp = RestraintsParameterisation(
        detector_parameterisations=[det_param],
        beam_parameterisations=[s0_param],
        xl_orientation_parameterisations=[xlo_param],
        xl_unit_cell_parameterisations=[xluc_param],
    )

    # make a unit cell target
    sigma = 1.0
    uc = mycrystal.get_unit_cell().parameters()
    target_uc = [random.gauss(e, sigma) for e in uc]

    rp.add_restraints_to_target_xl_unit_cell(experiment_id=0,
                                             values=target_uc,
                                             sigma=[sigma] * 6)

    # get analytical values and gradients
    vals, grads, weights = rp.get_residuals_gradients_and_weights()
    assert len(vals) == rp.num_residuals

    # get finite difference gradients
    p_vals = pred_param.get_param_vals()
    deltas = [1.0e-7] * len(p_vals)

    fd_grad = []

    for i, delta in enumerate(deltas):
        val = p_vals[i]

        p_vals[i] -= delta / 2.0
        pred_param.set_param_vals(p_vals)

        rev_state, foo, bar = rp.get_residuals_gradients_and_weights()
        rev_state = flex.double(rev_state)

        p_vals[i] += delta
        pred_param.set_param_vals(p_vals)

        fwd_state, foo, bar = rp.get_residuals_gradients_and_weights()
        fwd_state = flex.double(fwd_state)

        p_vals[i] = val

        fd = (fwd_state - rev_state) / delta
        fd_grad.append(fd)

    # for comparison, fd_grad is a list of flex.doubles, each of which corresponds
    # to a column of the sparse matrix grads.
    for i, fd in enumerate(fd_grad):
        # extract dense column from the sparse matrix
        an = grads.col(i).as_dense_vector()

        assert an == pytest.approx(fd, abs=1e-5)
예제 #8
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#############################
# Setup experimental models #
#############################

args = sys.argv[1:]
# make a small cell to speed up calculations
overrides = """geometry.parameters.crystal.a.length.range = 10 15
geometry.parameters.crystal.b.length.range = 10 15
geometry.parameters.crystal.c.length.range = 10 15"""

master_phil = parse("""
    include scope dials.test.algorithms.refinement.geometry_phil
    """,
                    process_includes=True)

models = Extract(master_phil, overrides, cmdline_args=args)

mydetector = models.detector
mygonio = models.goniometer
mycrystal = models.crystal
mybeam = models.beam

# Build a mock scan for a 180 degree sweep of 0.1 degree images
sf = ScanFactory()
myscan = sf.make_scan(image_range=(1, 1800),
                      exposure_times=0.1,
                      oscillation=(0, 0.1),
                      epochs=range(1800),
                      deg=True)
sweep_range = myscan.get_oscillation_range(deg=False)
im_width = myscan.get_oscillation(deg=False)[1]
예제 #9
0
def test(args=[]):
    # Python and cctbx imports
    from math import pi
    import random
    from scitbx import matrix
    from scitbx.array_family import flex
    from libtbx.phil import parse
    from libtbx.test_utils import approx_equal

    # Experimental model builder
    from dials.test.algorithms.refinement.setup_geometry import Extract

    # We will set up a mock scan and a mock experiment list
    from dxtbx.model import ScanFactory
    from dxtbx.model.experiment_list import ExperimentList, Experiment

    # Model parameterisations
    from dials.algorithms.refinement.parameterisation.detector_parameters import (
        DetectorParameterisationSinglePanel, )
    from dials.algorithms.refinement.parameterisation.beam_parameters import (
        BeamParameterisation, )
    from dials.algorithms.refinement.parameterisation.crystal_parameters import (
        CrystalOrientationParameterisation,
        CrystalUnitCellParameterisation,
    )

    # Reflection prediction
    from dials.algorithms.spot_prediction import IndexGenerator, ray_intersection
    from dials.algorithms.refinement.prediction.managed_predictors import (
        ScansRayPredictor,
        ScansExperimentsPredictor,
    )
    from cctbx.sgtbx import space_group, space_group_symbols

    # Parameterisation of the prediction equation
    from dials.algorithms.refinement.parameterisation.prediction_parameters import (
        XYPhiPredictionParameterisation, )

    # Imports for the target function
    from dials.algorithms.refinement.target import (
        LeastSquaresPositionalResidualWithRmsdCutoff, )
    from dials.algorithms.refinement.reflection_manager import ReflectionManager

    # Local functions
    def random_direction_close_to(vector, sd=0.5):
        return vector.rotate_around_origin(
            matrix.col((random.random(), random.random(),
                        random.random())).normalize(),
            random.gauss(0, sd),
            deg=True,
        )

    #############################
    # Setup experimental models #
    #############################

    # make a small cell to speed up calculations
    overrides = """geometry.parameters.crystal.a.length.range = 10 15
  geometry.parameters.crystal.b.length.range = 10 15
  geometry.parameters.crystal.c.length.range = 10 15"""

    master_phil = parse(
        """
      include scope dials.test.algorithms.refinement.geometry_phil
      """,
        process_includes=True,
    )

    models = Extract(master_phil, overrides, cmdline_args=args)

    mydetector = models.detector
    mygonio = models.goniometer
    mycrystal = models.crystal
    mybeam = models.beam

    # Build a mock scan for a 180 degree sweep of 0.1 degree images
    sf = ScanFactory()
    myscan = sf.make_scan(
        image_range=(1, 1800),
        exposure_times=0.1,
        oscillation=(0, 0.1),
        epochs=list(range(1800)),
        deg=True,
    )
    sweep_range = myscan.get_oscillation_range(deg=False)
    im_width = myscan.get_oscillation(deg=False)[1]
    assert sweep_range == (0.0, pi)
    assert approx_equal(im_width, 0.1 * pi / 180.0)

    experiments = ExperimentList()
    experiments.append(
        Experiment(
            beam=mybeam,
            detector=mydetector,
            goniometer=mygonio,
            scan=myscan,
            crystal=mycrystal,
            imageset=None,
        ))

    ###########################
    # Parameterise the models #
    ###########################

    det_param = DetectorParameterisationSinglePanel(mydetector)
    s0_param = BeamParameterisation(mybeam, mygonio)
    xlo_param = CrystalOrientationParameterisation(mycrystal)
    xluc_param = CrystalUnitCellParameterisation(mycrystal)

    ########################################################################
    # Link model parameterisations together into a parameterisation of the #
    # prediction equation                                                  #
    ########################################################################

    pred_param = XYPhiPredictionParameterisation(experiments, [det_param],
                                                 [s0_param], [xlo_param],
                                                 [xluc_param])

    ################################
    # Apply known parameter shifts #
    ################################

    # shift detector by 0.2 mm each translation and 2 mrad each rotation
    det_p_vals = det_param.get_param_vals()
    p_vals = [
        a + b for a, b in zip(det_p_vals, [2.0, 2.0, 2.0, 2.0, 2.0, 2.0])
    ]
    det_param.set_param_vals(p_vals)

    # shift beam by 2 mrad in one axis
    s0_p_vals = s0_param.get_param_vals()
    p_vals = list(s0_p_vals)
    p_vals[1] += 2.0
    s0_param.set_param_vals(p_vals)

    # rotate crystal a bit (=2 mrad each rotation)
    xlo_p_vals = xlo_param.get_param_vals()
    p_vals = [a + b for a, b in zip(xlo_p_vals, [2.0, 2.0, 2.0])]
    xlo_param.set_param_vals(p_vals)

    #############################
    # Generate some reflections #
    #############################

    # All indices in a 2.0 Angstrom sphere
    resolution = 2.0
    index_generator = IndexGenerator(
        mycrystal.get_unit_cell(),
        space_group(space_group_symbols(1).hall()).type(),
        resolution,
    )
    indices = index_generator.to_array()

    # Predict rays within the sweep range
    ray_predictor = ScansRayPredictor(experiments, sweep_range)
    obs_refs = ray_predictor(indices)

    # Take only those rays that intersect the detector
    intersects = ray_intersection(mydetector, obs_refs)
    obs_refs = obs_refs.select(intersects)

    # Make a reflection predictor and re-predict for all these reflections. The
    # result is the same, but we gain also the flags and xyzcal.px columns
    ref_predictor = ScansExperimentsPredictor(experiments)
    obs_refs["id"] = flex.int(len(obs_refs), 0)
    obs_refs = ref_predictor(obs_refs)

    # Set 'observed' centroids from the predicted ones
    obs_refs["xyzobs.mm.value"] = obs_refs["xyzcal.mm"]

    # Invent some variances for the centroid positions of the simulated data
    im_width = 0.1 * pi / 180.0
    px_size = mydetector[0].get_pixel_size()
    var_x = flex.double(len(obs_refs), (px_size[0] / 2.0)**2)
    var_y = flex.double(len(obs_refs), (px_size[1] / 2.0)**2)
    var_phi = flex.double(len(obs_refs), (im_width / 2.0)**2)
    obs_refs["xyzobs.mm.variance"] = flex.vec3_double(var_x, var_y, var_phi)

    ###############################
    # Undo known parameter shifts #
    ###############################

    s0_param.set_param_vals(s0_p_vals)
    det_param.set_param_vals(det_p_vals)
    xlo_param.set_param_vals(xlo_p_vals)

    #####################################
    # Select reflections for refinement #
    #####################################

    refman = ReflectionManager(obs_refs, experiments)

    ##############################
    # Set up the target function #
    ##############################

    # Redefine the reflection predictor to use the type expected by the Target class
    ref_predictor = ScansExperimentsPredictor(experiments)

    mytarget = LeastSquaresPositionalResidualWithRmsdCutoff(
        experiments,
        ref_predictor,
        refman,
        pred_param,
        restraints_parameterisation=None)

    # get the functional and gradients
    mytarget.predict()
    L, dL_dp, curvs = mytarget.compute_functional_gradients_and_curvatures()

    ####################################
    # Do FD calculation for comparison #
    ####################################

    # function for calculating finite difference gradients of the target function
    def get_fd_gradients(target, pred_param, deltas):
        """Calculate centered finite difference gradients for each of the
        parameters of the target function.

        "deltas" must be a sequence of the same length as the parameter list, and
        contains the step size for the difference calculations for each parameter.
        """

        p_vals = pred_param.get_param_vals()
        assert len(deltas) == len(p_vals)
        fd_grad = []
        fd_curvs = []

        for i in range(len(deltas)):
            val = p_vals[i]

            p_vals[i] -= deltas[i] / 2.0
            pred_param.set_param_vals(p_vals)
            target.predict()

            rev_state = target.compute_functional_gradients_and_curvatures()

            p_vals[i] += deltas[i]
            pred_param.set_param_vals(p_vals)

            target.predict()

            fwd_state = target.compute_functional_gradients_and_curvatures()

            # finite difference estimation of first derivatives
            fd_grad.append((fwd_state[0] - rev_state[0]) / deltas[i])

            # finite difference estimation of curvatures, using the analytical
            # first derivatives
            fd_curvs.append((fwd_state[1][i] - rev_state[1][i]) / deltas[i])

            # set parameter back to centred value
            p_vals[i] = val

        # return to the initial state
        pred_param.set_param_vals(p_vals)

        return fd_grad, fd_curvs

    # test normalised differences between FD and analytical calculations
    fdgrads = get_fd_gradients(mytarget, pred_param,
                               [1.0e-7] * len(pred_param))
    diffs = [a - b for a, b in zip(dL_dp, fdgrads[0])]
    norm_diffs = tuple([a / b for a, b in zip(diffs, fdgrads[0])])
    for e in norm_diffs:
        assert abs(e) < 0.001  # check differences less than 0.1%

    # test normalised differences between FD curvatures and analytical least
    # squares approximation. We don't expect this to be especially close
    if curvs:
        diffs = [a - b for a, b in zip(curvs, fdgrads[1])]
        norm_diffs = tuple([a / b for a, b in zip(diffs, fdgrads[1])])
        for e in norm_diffs:
            assert abs(e) < 0.1  # check differences less than 10%
예제 #10
0
def test2():
    '''Simple test with two triclinic crystals restrained to a target unit cell'''

    from math import pi
    from random import gauss
    from dials.test.algorithms.refinement.setup_geometry import Extract
    from dxtbx.model.experiment.experiment_list import ExperimentList, Experiment

    #### Import model parameterisations

    from dials.algorithms.refinement.parameterisation.prediction_parameters import \
        XYPhiPredictionParameterisation
    from dials.algorithms.refinement.parameterisation.detector_parameters import \
        DetectorParameterisationSinglePanel
    from dials.algorithms.refinement.parameterisation.beam_parameters import \
        BeamParameterisation
    from dials.algorithms.refinement.parameterisation.crystal_parameters import \
        CrystalOrientationParameterisation, \
        CrystalUnitCellParameterisation

    overrides = """geometry.parameters.crystal.a.length.range = 10 50
  geometry.parameters.crystal.b.length.range = 10 50
  geometry.parameters.crystal.c.length.range = 10 50"""

    master_phil = parse("""
      include scope dials.test.algorithms.refinement.geometry_phil
      """,
                        process_includes=True)

    models = Extract(master_phil, overrides)

    mydetector = models.detector
    mygonio = models.goniometer
    mycrystal = models.crystal
    # duplicate the crystal
    from copy import deepcopy
    mycrystal2 = deepcopy(mycrystal)
    mybeam = models.beam

    # Build a mock scan for a 72 degree sweep
    sweep_range = (0., pi / 5.)
    from dxtbx.model.scan import scan_factory
    sf = scan_factory()
    myscan = sf.make_scan(image_range=(1, 720),
                          exposure_times=0.1,
                          oscillation=(0, 0.1),
                          epochs=range(720),
                          deg=True)

    # Create parameterisations of these models
    det_param = DetectorParameterisationSinglePanel(mydetector)
    s0_param = BeamParameterisation(mybeam, mygonio)
    xlo_param = CrystalOrientationParameterisation(mycrystal)
    xluc_param = CrystalUnitCellParameterisation(mycrystal)
    xluc_param2 = CrystalUnitCellParameterisation(mycrystal2,
                                                  experiment_ids=[1])

    # Create an ExperimentList with the crystal duplicated
    experiments = ExperimentList()
    experiments.append(
        Experiment(beam=mybeam,
                   detector=mydetector,
                   goniometer=mygonio,
                   scan=myscan,
                   crystal=mycrystal,
                   imageset=None))
    experiments.append(
        Experiment(beam=mybeam,
                   detector=mydetector,
                   goniometer=mygonio,
                   scan=myscan,
                   crystal=mycrystal2,
                   imageset=None))

    # Build a prediction parameterisation
    pred_param = XYPhiPredictionParameterisation(
        experiments,
        detector_parameterisations=[det_param],
        beam_parameterisations=[s0_param],
        xl_orientation_parameterisations=[xlo_param],
        xl_unit_cell_parameterisations=[xluc_param, xluc_param2])

    # Build a restraints parameterisation
    rp = RestraintsParameterisation(
        detector_parameterisations=[det_param],
        beam_parameterisations=[s0_param],
        xl_orientation_parameterisations=[xlo_param],
        xl_unit_cell_parameterisations=[xluc_param, xluc_param2])

    # make a unit cell target
    sigma = 1.
    uc = mycrystal.get_unit_cell().parameters()
    target_uc = [gauss(e, sigma) for e in uc]

    rp.add_restraints_to_target_xl_unit_cell(experiment_id=0,
                                             values=target_uc,
                                             sigma=[sigma] * 6)
    rp.add_restraints_to_target_xl_unit_cell(experiment_id=1,
                                             values=target_uc,
                                             sigma=[sigma] * 6)

    # get analytical values and gradients
    vals, grads, weights = rp.get_residuals_gradients_and_weights()

    # get finite difference gradients
    p_vals = pred_param.get_param_vals()
    deltas = [1.e-7] * len(p_vals)

    fd_grad = []
    for i in range(len(deltas)):

        val = p_vals[i]

        p_vals[i] -= deltas[i] / 2.
        pred_param.set_param_vals(p_vals)

        rev_state, foo, bar = rp.get_residuals_gradients_and_weights()
        rev_state = flex.double(rev_state)

        p_vals[i] += deltas[i]
        pred_param.set_param_vals(p_vals)

        fwd_state, foo, bar = rp.get_residuals_gradients_and_weights()
        fwd_state = flex.double(fwd_state)

        p_vals[i] = val

        fd = (fwd_state - rev_state) / deltas[i]
        fd_grad.append(fd)

    # for comparison, fd_grad is a list of flex.doubles, each of which corresponds
    # to a column of the sparse matrix grads.
    for i, fd in enumerate(fd_grad):
        # extract dense column from the sparse matrix
        an = grads.col(i).as_dense_vector()
        assert approx_equal(an, fd, eps=1e-5)

    print "OK"
예제 #11
0
def test():
  from cctbx.sgtbx import space_group, space_group_symbols
  from libtbx.phil import parse
  from scitbx.array_family import flex

  ##### Import model builder

  from dials.test.algorithms.refinement.setup_geometry import Extract

  ##### Imports for reflection prediction

  from dials.algorithms.spot_prediction import IndexGenerator, ray_intersection
  from dxtbx.model.experiment_list import ExperimentList, Experiment
  from dials.algorithms.refinement.prediction import ScansRayPredictor, \
    ExperimentsPredictor

  #### Import model parameterisations

  from dials.algorithms.refinement.parameterisation.prediction_parameters import \
      XYPhiPredictionParameterisation
  from dials.algorithms.refinement.parameterisation.detector_parameters import \
      DetectorParameterisationSinglePanel
  from dials.algorithms.refinement.parameterisation.beam_parameters import \
      BeamParameterisation
  from dials.algorithms.refinement.parameterisation.crystal_parameters import \
      CrystalOrientationParameterisation, \
      CrystalUnitCellParameterisation
  from dials.algorithms.refinement.parameterisation.goniometer_parameters import \
      GoniometerParameterisation

  #### Create models

  overrides = """geometry.parameters.crystal.a.length.range = 10 50
  geometry.parameters.crystal.b.length.range = 10 50
  geometry.parameters.crystal.c.length.range = 10 50"""

  master_phil = parse("""
      include scope dials.test.algorithms.refinement.geometry_phil
      """, process_includes=True)

  models = Extract(master_phil, overrides)

  mydetector = models.detector
  mygonio = models.goniometer
  mycrystal = models.crystal
  mybeam = models.beam

  # Build a mock scan for a 72 degree sweep
  sweep_range = (0., math.pi/5.)
  from dxtbx.model import ScanFactory
  sf = ScanFactory()
  myscan = sf.make_scan(image_range = (1,720),
                        exposure_times = 0.1,
                        oscillation = (0, 0.1),
                        epochs = range(720),
                        deg = True)

  #### Create parameterisations of these models

  det_param = DetectorParameterisationSinglePanel(mydetector)
  s0_param = BeamParameterisation(mybeam, mygonio)
  xlo_param = CrystalOrientationParameterisation(mycrystal)
  xluc_param = CrystalUnitCellParameterisation(mycrystal)
  gon_param = GoniometerParameterisation(mygonio, mybeam)

  # Create an ExperimentList
  experiments = ExperimentList()
  experiments.append(Experiment(
        beam=mybeam, detector=mydetector, goniometer=mygonio, scan=myscan,
        crystal=mycrystal, imageset=None))

  #### Unit tests

  # Build a prediction parameterisation
  pred_param = XYPhiPredictionParameterisation(experiments,
                 detector_parameterisations = [det_param],
                 beam_parameterisations = [s0_param],
                 xl_orientation_parameterisations = [xlo_param],
                 xl_unit_cell_parameterisations = [xluc_param],
                 goniometer_parameterisations = [gon_param])

  # Generate reflections
  resolution = 2.0
  index_generator = IndexGenerator(mycrystal.get_unit_cell(),
                        space_group(space_group_symbols(1).hall()).type(),
                        resolution)
  indices = index_generator.to_array()

  # Predict rays within the sweep range
  ray_predictor = ScansRayPredictor(experiments, sweep_range)
  obs_refs = ray_predictor(indices)

  # Take only those rays that intersect the detector
  intersects = ray_intersection(mydetector, obs_refs)
  obs_refs = obs_refs.select(intersects)

  # Make a reflection predictor and re-predict for all these reflections. The
  # result is the same, but we gain also the flags and xyzcal.px columns
  ref_predictor = ExperimentsPredictor(experiments)
  obs_refs['id'] = flex.int(len(obs_refs), 0)
  obs_refs = ref_predictor(obs_refs)

  # Set 'observed' centroids from the predicted ones
  obs_refs['xyzobs.mm.value'] = obs_refs['xyzcal.mm']

  # Invent some variances for the centroid positions of the simulated data
  im_width = 0.1 * math.pi / 180.
  px_size = mydetector[0].get_pixel_size()
  var_x = flex.double(len(obs_refs), (px_size[0] / 2.)**2)
  var_y = flex.double(len(obs_refs), (px_size[1] / 2.)**2)
  var_phi = flex.double(len(obs_refs), (im_width / 2.)**2)
  obs_refs['xyzobs.mm.variance'] = flex.vec3_double(var_x, var_y, var_phi)

  # use a ReflectionManager to exclude reflections too close to the spindle
  from dials.algorithms.refinement.reflection_manager import ReflectionManager
  refman = ReflectionManager(obs_refs, experiments, outlier_detector=None)

  # Redefine the reflection predictor to use the type expected by the Target class
  ref_predictor = ExperimentsPredictor(experiments)

  # make a target to ensure reflections are predicted and refman is finalised
  from dials.algorithms.refinement.target import \
    LeastSquaresPositionalResidualWithRmsdCutoff
  target = LeastSquaresPositionalResidualWithRmsdCutoff(experiments,
      ref_predictor, refman, pred_param, restraints_parameterisation=None)

  # keep only those reflections that pass inclusion criteria and have predictions
  reflections = refman.get_matches()

  # get analytical gradients
  an_grads = pred_param.get_gradients(reflections)

  # get finite difference gradients
  p_vals = pred_param.get_param_vals()
  deltas = [1.e-7] * len(p_vals)

  for i, delta in enumerate(deltas):
    val = p_vals[i]

    p_vals[i] -= delta / 2.
    pred_param.set_param_vals(p_vals)

    ref_predictor(reflections)

    rev_state = reflections['xyzcal.mm'].deep_copy()

    p_vals[i] += delta
    pred_param.set_param_vals(p_vals)

    ref_predictor(reflections)

    fwd_state = reflections['xyzcal.mm'].deep_copy()
    p_vals[i] = val

    fd = (fwd_state - rev_state)
    x_grads, y_grads, phi_grads = fd.parts()
    x_grads /= delta
    y_grads /= delta
    phi_grads /= delta

    # compare with analytical calculation
    assert x_grads == pytest.approx(an_grads[i]["dX_dp"], abs=5.e-6)
    assert y_grads == pytest.approx(an_grads[i]["dY_dp"], abs=5.e-6)
    assert phi_grads == pytest.approx(an_grads[i]["dphi_dp"], abs=5.e-6)

  # return to the initial state
  pred_param.set_param_vals(p_vals)
예제 #12
0
# We will set up a mock scan
from dxtbx.model import ScanFactory

args = sys.argv[1:]

master_phil = parse("""
include scope dials.test.algorithms.refinement.geometry_phil
include scope dials.test.algorithms.refinement.minimiser_phil
""",
                    process_includes=True)

overrides = """geometry.parameters.crystal.a.length.range = 10 50
geometry.parameters.crystal.b.length.range = 10 50
geometry.parameters.crystal.c.length.range = 10 50"""

models = Extract(master_phil, local_overrides=overrides, cmdline_args=args)

mydetector = models.detector
mygonio = models.goniometer
mycrystal = models.crystal
mybeam = models.beam

#############################
# Generate some reflections #
#############################

# All indices in a 2.0 Angstrom sphere
resolution = 2.0
index_generator = IndexGenerator(
    mycrystal.get_unit_cell(),
    space_group(space_group_symbols(1).hall()).type(), resolution)