Beispiel #1
0
    def split(self, X, y=None, groups=None):

        # Generate the composition vectors
        frac_computer = ElementFraction()
        elem_fracs = frac_computer.featurize_many(list(map(Composition, X)),
                                                  pbar=False)

        # Generate the nearest-neighbor lookup tool
        neigh = NearestNeighbors(**self.nn_kwargs)
        neigh.fit(elem_fracs)

        # Generate a list of all entries
        all_inds = np.arange(0, len(X), 1)

        # Loop through each entry in X
        for i, x in enumerate(elem_fracs):

            # Get all the entries within the threshold distance of the test point
            too_close, = neigh.radius_neighbors([x],
                                                self.dist_threshold,
                                                return_distance=False)

            # Get the training set as "not these points"
            train_inds = np.setdiff1d(all_inds, too_close)

            yield train_inds, [i]
Beispiel #2
0
 def __init__(self, pbar=False):
     self.regressor = RandomForestRegressor(n_estimators=500, n_jobs=-1, verbose=3)
     self.stc = StrToComposition()
     ep = ElementProperty.from_preset("magpie")
     ef = ElementFraction()
     self.featurizer = MultipleFeaturizer([ep, ef])
     self.pbar = pbar
Beispiel #3
0
    def featurize(self, comp):
        """
        Get elemental property attributes

        Args:
            comp: Pymatgen composition object

        Returns:
            all_attributes: Specified property statistics of features
        """

        # First 103 features are element fractions, we can get these from the ElementFraction featurizer
        element_fraction_features = ElementFraction().featurize(comp)

        # Next 9 features are statistics on elemental properties
        elements, fractions = zip(*comp.element_composition.items())
        element_property_features = [0] * len(self._element_property_feature_labels)

        for i,feat in enumerate(self._element_property_feature_labels):
            stat = feat.split(" ")[0]
            attr = " ".join(feat.split(" ")[1:])

            elem_data = [self.data_source.get_elemental_property(e, attr) for e in elements]
            element_property_features[i] = self.pstats.calc_stat(elem_data, stat, fractions)

        # Final 8 features are statistics on valence orbitals, available from the ValenceOrbital featurizer
        valence_orbital_features = ValenceOrbital(orbitals=("s", "p", "d", "f"), props=("avg", "frac")).featurize(comp)

        return element_fraction_features+element_property_features+valence_orbital_features
Beispiel #4
0
def featurize_composition(df: pd.DataFrame) -> pd.DataFrame:
    """ Decorate input `pandas.DataFrame` of structures with composition
    features from matminer.

    Currently applies the set of all matminer composition features.

    Args:
        df (pandas.DataFrame): the input dataframe with `"structure"`
            column containing `pymatgen.Structure` objects.

    Returns:
        pandas.DataFrame: the decorated DataFrame.

    """
    logging.info("Applying composition featurizers...")
    df = df.copy()
    df['composition'] = df['structure'].apply(lambda s: s.composition)
    featurizer = MultipleFeaturizer([ElementProperty.from_preset("magpie"),
                                     AtomicOrbitals(),
                                     BandCenter(),
                                     # ElectronAffinity(), - This descriptor was not used in the paper preset
                                     Stoichiometry(),
                                     ValenceOrbital(),
                                     IonProperty(),
                                     ElementFraction(),
                                     TMetalFraction(),
                                     # CohesiveEnergy(), - This descriptor was not used in the paper preset
                                     Miedema(),
                                     YangSolidSolution(),
                                     AtomicPackingEfficiency(),
                                     ])

    df = featurizer.featurize_dataframe(df, "composition", multiindex=True, ignore_errors=True)
    df.columns = df.columns.map('|'.join).str.strip('|')

    ox_featurizer = MultipleFeaturizer([OxidationStates(),
                                        ElectronegativityDiff()
                                        ])

    df = CompositionToOxidComposition().featurize_dataframe(df, "Input Data|composition")

    df = ox_featurizer.featurize_dataframe(df, "composition_oxid", multiindex=True, ignore_errors=True)
    df = df.rename(columns={'Input Data': ''})
    df.columns = df.columns.map('|'.join).str.strip('|')

    _orbitals = {"s": 1, "p": 2, "d": 3, "f": 4}

    df['AtomicOrbitals|HOMO_character'] = df['AtomicOrbitals|HOMO_character'].map(_orbitals)
    df['AtomicOrbitals|LUMO_character'] = df['AtomicOrbitals|LUMO_character'].map(_orbitals)

    df['AtomicOrbitals|HOMO_element'] = df['AtomicOrbitals|HOMO_element'].apply(
        lambda x: -1 if not isinstance(x, str) else Element(x).Z
    )
    df['AtomicOrbitals|LUMO_element'] = df['AtomicOrbitals|LUMO_element'].apply(
        lambda x: -1 if not isinstance(x, str) else Element(x).Z
    )

    df = df.replace([np.inf, -np.inf, np.nan], 0)

    return clean_df(df)
Beispiel #5
0
    def __init__(self, threshold=0.01, n_nearest=(1, 3, 5), max_types=6):
        """
        Initialize the featurizer

        Args:
            threshold (float):Threshold to use for determining whether
                a cluster is efficiently packed.
            n_nearest ({int}): Number of nearest clusters to use when
                considering features
            max_types (int): Maximum number of atom types to consider when
                looking for efficient clusters. The process for finding
                efficient clusters very expensive for large numbers of types
        """

        # Store the options
        self.threshold = threshold
        self.n_nearest = n_nearest
        self.max_types = max_types

        # Tool to convert composition objects to fractions as a vector
        self._el_frac = ElementFraction()

        # Get the number of elements in the output of `_el_frac`
        self._n_elems = len(self._el_frac.featurize(Composition('H')))

        # Tool for looking up radii
        self._data_source = MagpieData()

        # Lookup table of ideal radius ratios
        self.ideal_ratio = dict(
            [(3, 0.154701), (4, 0.224745), (5, 0.361654), (6, 0.414214),
             (7, 0.518145), (8, 0.616517), (9, 0.709914), (10, 0.798907),
             (11, 0.884003), (12, 0.902113), (13, 0.976006), (14, 1.04733),
             (15, 1.11632), (16, 1.18318), (17, 1.2481), (18, 1.31123),
             (19, 1.37271), (20, 1.43267), (21, 1.49119), (22, 1.5484),
             (23, 1.60436), (24, 1.65915)])
Beispiel #6
0
class DeBreuck2020Featurizer(modnet.featurizers.MODFeaturizer):
    """ Featurizer presets used for the paper 'Machine learning
    materials properties for small datasets' by Pierre-Paul De Breuck,
    Geoffroy Hautier & Gian-Marco Rignanese, arXiv:2004.14766 (2020).

    Uses most of the featurizers implemented by matminer at the time of
    writing with their default hyperparameters and presets.

    """
    from matminer.featurizers.composition import (
        AtomicOrbitals,
        AtomicPackingEfficiency,
        BandCenter,
        # CohesiveEnergy, - This descriptor was not used in the paper preset
        # ElectronAffinity, - This descriptor was not used in the paper preset
        ElectronegativityDiff,
        ElementFraction,
        ElementProperty,
        IonProperty,
        Miedema,
        OxidationStates,
        Stoichiometry,
        TMetalFraction,
        ValenceOrbital,
        YangSolidSolution,
    )
    from matminer.featurizers.structure import (
        # BagofBonds, - This descriptor was not used in the paper preset
        BondFractions,
        ChemicalOrdering,
        CoulombMatrix,
        DensityFeatures,
        EwaldEnergy,
        GlobalSymmetryFeatures,
        MaximumPackingEfficiency,
        # PartialRadialDistributionFunction,
        RadialDistributionFunction,
        SineCoulombMatrix,
        StructuralHeterogeneity,
        XRDPowderPattern,
    )

    from matminer.featurizers.site import (
        AGNIFingerprints,
        AverageBondAngle,
        AverageBondLength,
        BondOrientationalParameter,
        ChemEnvSiteFingerprint,
        CoordinationNumber,
        CrystalNNFingerprint,
        GaussianSymmFunc,
        GeneralizedRadialDistributionFunction,
        LocalPropertyDifference,
        OPSiteFingerprint,
        VoronoiFingerprint,
    )

    composition_featurizers = (
        AtomicOrbitals(),
        AtomicPackingEfficiency(),
        BandCenter(),
        ElementFraction(),
        ElementProperty.from_preset("magpie"),
        IonProperty(),
        Miedema(),
        Stoichiometry(),
        TMetalFraction(),
        ValenceOrbital(),
        YangSolidSolution(),
    )

    oxide_composition_featurizers = (
        ElectronegativityDiff(),
        OxidationStates(),
    )

    structure_featurizers = (
        DensityFeatures(),
        GlobalSymmetryFeatures(),
        RadialDistributionFunction(),
        CoulombMatrix(),
        # PartialRadialDistributionFunction(),
        SineCoulombMatrix(),
        EwaldEnergy(),
        BondFractions(),
        StructuralHeterogeneity(),
        MaximumPackingEfficiency(),
        ChemicalOrdering(),
        XRDPowderPattern(),
        # BagofBonds(),
    )
    site_featurizers = (
        AGNIFingerprints(),
        AverageBondAngle(VoronoiNN()),
        AverageBondLength(VoronoiNN()),
        BondOrientationalParameter(),
        ChemEnvSiteFingerprint.from_preset("simple"),
        CoordinationNumber(),
        CrystalNNFingerprint.from_preset("ops"),
        GaussianSymmFunc(),
        GeneralizedRadialDistributionFunction.from_preset("gaussian"),
        LocalPropertyDifference(),
        OPSiteFingerprint(),
        VoronoiFingerprint(),
    )

    def featurize_composition(self, df):
        """ Applies the preset composition featurizers to the input dataframe,
        renames some fields and cleans the output dataframe.

        """
        df = super().featurize_composition(df)

        _orbitals = {"s": 1, "p": 2, "d": 3, "f": 4}
        df['AtomicOrbitals|HOMO_character'] = df[
            'AtomicOrbitals|HOMO_character'].map(_orbitals)
        df['AtomicOrbitals|LUMO_character'] = df[
            'AtomicOrbitals|LUMO_character'].map(_orbitals)

        df['AtomicOrbitals|HOMO_element'] = df[
            'AtomicOrbitals|HOMO_element'].apply(
                lambda x: -1 if not isinstance(x, str) else Element(x).Z)
        df['AtomicOrbitals|LUMO_element'] = df[
            'AtomicOrbitals|LUMO_element'].apply(
                lambda x: -1 if not isinstance(x, str) else Element(x).Z)

        df = df.replace([np.inf, -np.inf, np.nan], 0)

        return modnet.featurizers.clean_df(df)

    def featurize_structure(self, df):
        """ Applies the preset structural featurizers to the input dataframe,
        renames some fields and cleans the output dataframe.

        """
        df = super().featurize_structure(df)

        dist = df[
            "RadialDistributionFunction|radial distribution function"].iloc[0][
                'distances'][:50]
        for i, d in enumerate(dist):
            _rdf_key = "RadialDistributionFunction|radial distribution function|d_{:.2f}".format(
                d)
            df[_rdf_key] = df[
                "RadialDistributionFunction|radial distribution function"].apply(
                    lambda x: x['distribution'][i])

        df = df.drop("RadialDistributionFunction|radial distribution function",
                     axis=1)

        _crystal_system = {
            "cubic": 1,
            "tetragonal": 2,
            "orthorombic": 3,
            "hexagonal": 4,
            "trigonal": 5,
            "monoclinic": 6,
            "triclinic": 7
        }

        def _int_map(x):
            if x == np.nan:
                return 0
            elif x:
                return 1
            else:
                return 0

        df["GlobalSymmetryFeatures|crystal_system"] = df[
            "GlobalSymmetryFeatures|crystal_system"].map(_crystal_system)
        df["GlobalSymmetryFeatures|is_centrosymmetric"] = df[
            "GlobalSymmetryFeatures|is_centrosymmetric"].map(_int_map)

        return modnet.featurizers.clean_df(df)

    def featurize_site(self, df):
        """ Applies the preset site featurizers to the input dataframe,
        renames some fields and cleans the output dataframe.

        """

        # rename some features for backwards compatibility with pretrained models
        aliases = {
            "GeneralizedRadialDistributionFunction": "GeneralizedRDF",
            "AGNIFingerprints": "AGNIFingerPrint",
            "BondOrientationalParameter": "BondOrientationParameter",
            "GaussianSymmFunc": "ChemEnvSiteFingerprint|GaussianSymmFunc",
        }
        df = super().featurize_site(df, aliases=aliases)
        df = df.loc[:, (df != 0).any(axis=0)]

        return modnet.featurizers.clean_df(df)
Beispiel #7
0
    def test_ape(self):
        f = AtomicPackingEfficiency()
        ef = ElementFraction()
        ef.set_n_jobs(1)

        # Test the APE calculation routines
        self.assertAlmostEqual(1.11632, f.get_ideal_radius_ratio(15))
        self.assertAlmostEqual(0.154701, f.get_ideal_radius_ratio(2))
        self.assertAlmostEqual(1.65915, f.get_ideal_radius_ratio(27))
        self.assertAlmostEqual(15, f.find_ideal_cluster_size(1.116)[0])
        self.assertAlmostEqual(3, f.find_ideal_cluster_size(0.1)[0])
        self.assertAlmostEqual(24, f.find_ideal_cluster_size(2)[0])

        # Test the nearest neighbor lookup tool
        nn_lookup = f.create_cluster_lookup_tool(
            [Element('Cu'), Element('Zr')])

        #  Check that the table gets the correct structures
        stable_clusters = [
            Composition('CuZr10'),
            Composition('Cu6Zr6'),
            Composition('Cu8Zr5'),
            Composition('Cu13Zr1'),
            Composition('Cu3Zr12'),
            Composition('Cu8Zr8'),
            Composition('Cu12Zr5'),
            Composition('Cu17Zr')
        ]
        ds, _ = nn_lookup.kneighbors(ef.featurize_many(stable_clusters),
                                     n_neighbors=1)
        self.assertArrayAlmostEqual([[0]] * 8, ds)
        self.assertEqual(8, nn_lookup._fit_X.shape[0])

        # Swap the order of the clusters, make sure it gets the same list
        nn_lookup_swapped = f.create_cluster_lookup_tool(
            [Element('Zr'), Element('Cu')])
        self.assertArrayAlmostEqual(sorted(nn_lookup._fit_X.tolist()),
                                    sorted(nn_lookup_swapped._fit_X.tolist()))

        # Make sure we had a cache hit
        self.assertEqual(1, f._create_cluster_lookup_tool.cache_info().misses)
        self.assertEqual(1, f._create_cluster_lookup_tool.cache_info().hits)

        # Change the tolerance, see if it changes the results properly
        f.threshold = 0.002
        nn_lookup = f.create_cluster_lookup_tool(
            [Element('Cu'), Element('Zr')])
        self.assertEqual(2, nn_lookup._fit_X.shape[0])
        ds, _ = nn_lookup.kneighbors(ef.featurize_many(
            [Composition('CuZr10'),
             Composition('Cu3Zr12')]),
                                     n_neighbors=1)
        self.assertArrayAlmostEqual([[0]] * 2, ds)

        # Make sure we had a cache miss
        self.assertEqual(2, f._create_cluster_lookup_tool.cache_info().misses)
        self.assertEqual(1, f._create_cluster_lookup_tool.cache_info().hits)

        # Compute the distances from Cu50Zr50
        mean_dists = f.compute_nearest_cluster_distance(Composition('CuZr'))
        self.assertArrayAlmostEqual([0.424264, 0.667602, 0.800561],
                                    mean_dists,
                                    decimal=6)

        # Compute the optimal APE for Cu50Zr50
        self.assertArrayAlmostEqual([0.000233857, 0.003508794],
                                    f.compute_simultaneous_packing_efficiency(
                                        Composition('Cu50Zr50')))

        # Test the dataframe calculator
        df = pd.DataFrame({'comp': [Composition('CuZr')]})
        df = f.featurize_dataframe(df, 'comp')

        self.assertEqual(6, len(df.columns))
        self.assertIn('dist from 5 clusters |APE| < 0.002', df.columns)

        self.assertAlmostEqual(0.003508794,
                               df['mean abs simul. packing efficiency'][0])

        # Make sure it works with composition that do not match any efficient clusters
        feat = f.compute_nearest_cluster_distance(Composition('Al'))
        self.assertArrayAlmostEqual([1] * 3, feat)
Beispiel #8
0
 def test_fraction(self):
     df_frac = ElementFraction().featurize_dataframe(self.df,
                                                     col_id="composition")
     self.assertEqual(df_frac["O"][0], 0.6)
     self.assertEqual(df_frac["Fe"][0], 0.4)
Beispiel #9
0
class FUTURE_PROSPECTS_2021(featurizer.extendedMODFeaturizer):

    from matminer.featurizers.composition import (
        AtomicOrbitals,
        AtomicPackingEfficiency,
        BandCenter,
        CohesiveEnergy,
        ElectronAffinity,
        ElectronegativityDiff,
        ElementFraction,
        ElementProperty,
        IonProperty,
        Miedema,
        OxidationStates,
        Stoichiometry,
        TMetalFraction,
        ValenceOrbital,
        YangSolidSolution,
    )
    from matminer.featurizers.structure import (
        BagofBonds,
        BondFractions,
        ChemicalOrdering,
        CoulombMatrix,
        DensityFeatures,
        EwaldEnergy,
        GlobalSymmetryFeatures,
        MaximumPackingEfficiency,
        PartialRadialDistributionFunction,
        RadialDistributionFunction,
        SineCoulombMatrix,
        StructuralHeterogeneity,
        XRDPowderPattern,
    )

    from matminer.featurizers.site import (
        AGNIFingerprints,
        AverageBondAngle,
        AverageBondLength,
        BondOrientationalParameter,
        ChemEnvSiteFingerprint,
        CoordinationNumber,
        CrystalNNFingerprint,
        GaussianSymmFunc,
        GeneralizedRadialDistributionFunction,
        LocalPropertyDifference,
        OPSiteFingerprint,
        VoronoiFingerprint,
    )
    from matminer.featurizers.dos import (
        DOSFeaturizer,
        SiteDOS,
        Hybridization,
        DosAsymmetry,
    )
    from matminer.featurizers.bandstructure import (
        BandFeaturizer,
        BranchPointEnergy
    )

    composition_featurizers = (
        AtomicOrbitals(),
        AtomicPackingEfficiency(),
        BandCenter(),
        ElementFraction(),
        ElementProperty.from_preset("magpie"),
        IonProperty(),
        Miedema(),
        Stoichiometry(),
        TMetalFraction(),
        ValenceOrbital(),
        YangSolidSolution(),
    )

    oxid_composition_featurizers = (
        ElectronegativityDiff(),
        OxidationStates(),
    )

    structure_featurizers = (
        DensityFeatures(),
        GlobalSymmetryFeatures(),
        RadialDistributionFunction(),
        CoulombMatrix(),
        #PartialRadialDistributionFunction(), #Introduces a large amount of features
        SineCoulombMatrix(),
        EwaldEnergy(),
        BondFractions(),
        StructuralHeterogeneity(),
        MaximumPackingEfficiency(),
        ChemicalOrdering(),
        XRDPowderPattern(),
    )
    site_featurizers = (
        AGNIFingerprints(),
        AverageBondAngle(VoronoiNN()),
        AverageBondLength(VoronoiNN()),
        BondOrientationalParameter(),
        ChemEnvSiteFingerprint.from_preset("simple"),
        CoordinationNumber(),
        CrystalNNFingerprint.from_preset("ops"),
        GaussianSymmFunc(),
        GeneralizedRadialDistributionFunction.from_preset("gaussian"),
        LocalPropertyDifference(),
        OPSiteFingerprint(),
        VoronoiFingerprint(),
    )

    dos_featurizers = (
        DOSFeaturizer(),
        SiteDOS(),
        Hybridization()
    )

    band_featurizers = (
        BandFeaturizer(),
        BranchPointEnergy()
    )
    def __init__(self, n_jobs=None):
            self._n_jobs = n_jobs

    def featurize_composition(self, df):
        """Applies the preset composition featurizers to the input dataframe,
        renames some fields and cleans the output dataframe.
        """
        df = super().featurize_composition(df)

        _orbitals = {"s": 1, "p": 2, "d": 3, "f": 4}
        df["AtomicOrbitals|HOMO_character"] = df["AtomicOrbitals|HOMO_character"].map(
            _orbitals
        )
        df["AtomicOrbitals|LUMO_character"] = df["AtomicOrbitals|LUMO_character"].map(
            _orbitals
        )

        df["AtomicOrbitals|HOMO_element"] = df["AtomicOrbitals|HOMO_element"].apply(
            lambda x: -1 if not isinstance(x, str) else Element(x).Z
        )
        df["AtomicOrbitals|LUMO_element"] = df["AtomicOrbitals|LUMO_element"].apply(
            lambda x: -1 if not isinstance(x, str) else Element(x).Z
        )

        return clean_df(df)

    def featurize_structure(self, df):
        """Applies the preset structural featurizers to the input dataframe,
        renames some fields and cleans the output dataframe.
        """
        df = super().featurize_structure(df)

        dist = df["RadialDistributionFunction|radial distribution function"].iloc[0][
            "distances"
        ][:50]
        for i, d in enumerate(dist):
            _rdf_key = "RadialDistributionFunction|radial distribution function|d_{:.2f}".format(
                d
            )
            df[_rdf_key] = df[
                "RadialDistributionFunction|radial distribution function"
            ].apply(lambda x: x["distribution"][i])

        df = df.drop("RadialDistributionFunction|radial distribution function", axis=1)

        _crystal_system = {
            "cubic": 1,
            "tetragonal": 2,
            "orthorombic": 3,
            "hexagonal": 4,
            "trigonal": 5,
            "monoclinic": 6,
            "triclinic": 7,
        }

        def _int_map(x):
            if x == np.nan:
                return 0
            elif x:
                return 1
            else:
                return 0

        df["GlobalSymmetryFeatures|crystal_system"] = df[
            "GlobalSymmetryFeatures|crystal_system"
        ].map(_crystal_system)
        df["GlobalSymmetryFeatures|is_centrosymmetric"] = df[
            "GlobalSymmetryFeatures|is_centrosymmetric"
        ].map(_int_map)

        return clean_df(df)

    def featurize_dos(self, df):
        """Applies the presetdos featurizers to the input dataframe,
        renames some fields and cleans the output dataframe.
        """

        df = super().featurize_dos(df)


        hotencodeColumns = ["DOSFeaturizer|vbm_specie_1","DOSFeaturizer|cbm_specie_1"]

        one_hot = pd.get_dummies(df[hotencodeColumns])
        df = df.drop(hotencodeColumns, axis = 1).join(one_hot)

        _orbitals = {"s": 1, "p": 2, "d": 3, "f": 4}

        df["DOSFeaturizer|vbm_character_1"] = df[
           "DOSFeaturizer|vbm_character_1"
           ].map(_orbitals)
        df["DOSFeaturizer|cbm_character_1"] = df[
           "DOSFeaturizer|cbm_character_1"
           ].map(_orbitals)

        # Splitting one feature into several floating features
        # e.g. number;number;number into three columns
        splitColumns = ["DOSFeaturizer|cbm_location_1", "DOSFeaturizer|vbm_location_1"]

        for column in splitColumns:
            try:
                newColumns = df[column].str.split(";", n = 2, expand = True)
                for i in range(0,3):
                    df[column + "_" + str(i)] = np.array(newColumns[i]).astype(np.float)
            except:
                continue
        df = df.drop(splitColumns, axis=1)
        df = df.drop(["dos"], axis=1)
        return clean_df(df)

    def featurize_bandstructure(self, df):
        """Applies the preset band structure featurizers to the input dataframe,
        renames some fields and cleans the output dataframe.
        """

        df = super().featurize_bandstructure(df)

        def _int_map(x):
            if str(x) == "False":
                return 0
            elif str(x) == "True":
                return 1

        df["BandFeaturizer|is_gap_direct"] = df[
            "BandFeaturizer|is_gap_direct"
        ].map(_int_map)


        df = df.drop(["bandstructure"], axis=1)

        return clean_df(df)


    def featurize_site(self, df):
        """Applies the preset site featurizers to the input dataframe,
        renames some fields and cleans the output dataframe.
        """

        aliases = {
            "GeneralizedRadialDistributionFunction": "GeneralizedRDF",
            "AGNIFingerprints": "AGNIFingerPrint",
            "BondOrientationalParameter": "BondOrientationParameter",
            "GaussianSymmFunc": "ChemEnvSiteFingerprint|GaussianSymmFunc",
        }
        df = super().featurize_site(df, aliases=aliases)
        df = df.loc[:, (df != 0).any(axis=0)]

        return clean_df(df)
Beispiel #10
0
    def test_ape(self):
        f = AtomicPackingEfficiency()
        ef = ElementFraction()
        ef.set_n_jobs(1)

        # Test the APE calculation routines
        self.assertAlmostEqual(1.11632, f.get_ideal_radius_ratio(15))
        self.assertAlmostEqual(0.154701, f.get_ideal_radius_ratio(2))
        self.assertAlmostEqual(1.65915, f.get_ideal_radius_ratio(27))
        self.assertAlmostEqual(15, f.find_ideal_cluster_size(1.116)[0])
        self.assertAlmostEqual(3, f.find_ideal_cluster_size(0.1)[0])
        self.assertAlmostEqual(24, f.find_ideal_cluster_size(2)[0])

        # Test the nearest neighbor lookup tool
        nn_lookup = f.create_cluster_lookup_tool([Element('Cu'),
                                                  Element('Zr')])

        #  Check that the table gets the correct structures
        stable_clusters = [Composition('CuZr10'), Composition('Cu6Zr6'),
                           Composition('Cu8Zr5'), Composition('Cu13Zr1'),
                           Composition('Cu3Zr12'), Composition('Cu8Zr8'),
                           Composition('Cu12Zr5'), Composition('Cu17Zr')]
        ds, _ = nn_lookup.kneighbors(
            ef.featurize_many(stable_clusters),
            n_neighbors=1)
        self.assertArrayAlmostEqual([[0]]*8, ds)
        self.assertEqual(8, nn_lookup._fit_X.shape[0])

        # Swap the order of the clusters, make sure it gets the same list
        nn_lookup_swapped = f.create_cluster_lookup_tool([Element('Zr'),
                                                          Element('Cu')])
        self.assertArrayAlmostEqual(sorted(nn_lookup._fit_X.tolist()),
                                    sorted(nn_lookup_swapped._fit_X.tolist()))

        # Make sure we had a cache hit
        self.assertEqual(1, f._create_cluster_lookup_tool.cache_info().misses)
        self.assertEqual(1, f._create_cluster_lookup_tool.cache_info().hits)

        # Change the tolerance, see if it changes the results properly
        f.threshold = 0.002
        nn_lookup = f.create_cluster_lookup_tool([Element('Cu'),
                                                  Element('Zr')])
        self.assertEqual(2, nn_lookup._fit_X.shape[0])
        ds, _ = nn_lookup.kneighbors(
            ef.featurize_many([Composition('CuZr10'), Composition('Cu3Zr12')]),
            n_neighbors=1)
        self.assertArrayAlmostEqual([[0]]*2, ds)

        # Make sure we had a cache miss
        self.assertEqual(2, f._create_cluster_lookup_tool.cache_info().misses)
        self.assertEqual(1, f._create_cluster_lookup_tool.cache_info().hits)

        # Compute the distances from Cu50Zr50
        mean_dists = f.compute_nearest_cluster_distance(Composition('CuZr'))
        self.assertArrayAlmostEqual([0.424264, 0.667602, 0.800561], mean_dists,
                                    decimal=6)

        # Compute the optimal APE for Cu50Zr50
        self.assertArrayAlmostEqual([0.000233857, 0.003508794],
                                    f.compute_simultaneous_packing_efficiency(
                                        Composition('Cu50Zr50')
                                    ))

        # Test the dataframe calculator
        df = pd.DataFrame({'comp': [Composition('CuZr')]})
        f.featurize_dataframe(df, 'comp')

        self.assertEqual(6, len(df.columns))
        self.assertIn('dist from 5 clusters |APE| < 0.002', df.columns)

        self.assertAlmostEqual(0.003508794,
                               df['mean abs simul. packing efficiency'][0])

        # Make sure it works with composition that do not match any efficient clusters
        feat = f.compute_nearest_cluster_distance(Composition('Al'))
        self.assertArrayAlmostEqual([1]*3, feat)
Beispiel #11
0
class AtomicPackingEfficiency(BaseFeaturizer):
    """
    Packing efficiency based on a geometric theory of the amorphous packing
    of hard spheres.

    This featurizer computes two different kinds of the features. The first
    relate to the distance between a composition and the composition of
    the clusters of atoms expected to be efficiently packed based on a
    theory from
    `Laws et al.<http://www.nature.com/doifinder/10.1038/ncomms9123>`_.
    The second corresponds to the packing efficiency of a system if all atoms
    in the alloy are simultaneously as efficiently-packed as possible.

    The packing efficiency in these models is based on the Atomic Packing
    Efficiency (APE), which measures the difference between the ratio of
    the radii of the central atom to its neighbors and the ideal ratio
    of a cluster with the same number of atoms that has optimal packing
    efficiency. If the difference between the ratios is too large, the APE is
    positive. If the difference is too small, the APE is negative.

    Features:
        dist from {k} clusters |APE| < {thr} - The distance between an
            alloy composition and the k clusters that have a packing efficiency
            below thr from ideal
        mean simul. packing efficiency - Mean packing efficiency of all atoms.
            The packing efficiency is measured with respect to ideal (0)
        mean abs simul. packing efficiency - Mean absolute value of the
            packing efficiencies. Closer to zero is more efficiently packed

    References:
        [1] K.J. Laws, D.B. Miracle, M. Ferry, A predictive structural model
        for bulk metallic glasses, Nat. Commun. 6 (2015) 8123. doi:10.1038/ncomms9123.
    """

    def __init__(self, threshold=0.01, n_nearest=(1, 3, 5), max_types=6):
        """
        Initialize the featurizer

        Args:
            threshold (float):Threshold to use for determining whether
                a cluster is efficiently packed.
            n_nearest ({int}): Number of nearest clusters to use when
                considering features
            max_types (int): Maximum number of atom types to consider when
                looking for efficient clusters. The process for finding
                efficient clusters very expensive for large numbers of types
        """

        # Store the options
        self.threshold = threshold
        self.n_nearest = n_nearest
        self.max_types = max_types

        # Tool to convert composition objects to fractions as a vector
        self._el_frac = ElementFraction()

        # Get the number of elements in the output of `_el_frac`
        self._n_elems = len(self._el_frac.featurize(Composition('H')))

        # Tool for looking up radii
        self._data_source = MagpieData()

        # Lookup table of ideal radius ratios
        self.ideal_ratio = dict(
            [(3, 0.154701), (4, 0.224745), (5, 0.361654), (6, 0.414214),
             (7, 0.518145), (8, 0.616517), (9, 0.709914), (10, 0.798907),
             (11, 0.884003), (12, 0.902113), (13, 0.976006), (14, 1.04733),
             (15, 1.11632), (16, 1.18318), (17, 1.2481), (18, 1.31123),
             (19, 1.37271), (20, 1.43267), (21, 1.49119), (22, 1.5484),
             (23, 1.60436), (24, 1.65915)])

    def __hash__(self):
        return hash(self.threshold)

    def __eq__(self, other):
        if isinstance(other, AtomicPackingEfficiency):
            return self.get_params() == other.get_params()

    def featurize(self, comp):
        return list(self.compute_simultaneous_packing_efficiency(comp)) + \
               self.compute_nearest_cluster_distance(comp)

    def feature_labels(self):
        return ['mean simul. packing efficiency',
                'mean abs simul. packing efficiency'] + [
                   f"dist from {k} clusters |APE| < {self.threshold:.3f}"
                   for k in self.n_nearest]

    def citations(self):
        return ["@article{Laws2015,"
                "author = {Laws, K. J. and Miracle, D. B. and Ferry, M.},"
                "doi = {10.1038/ncomms9123},"
                "journal = {Nature Communications},"
                "pages = {8123},"
                "title = {{A predictive structural model for bulk metallic glasses}},"
                "url = {http://www.nature.com/doifinder/10.1038/ncomms9123},"
                "volume = {6},"
                "year = {2015}"]

    def implementors(self):
        return ['Logan Ward']

    def compute_simultaneous_packing_efficiency(self, comp):
        """Compute the packing efficiency of the system when the neighbor
        shell of each atom has the same composition as the alloy. When this
        criterion is satisfied, it is possible for every atom in this system
        to be simultaneously as efficiently-packed as possible.

        Args:
            comp (Composition): Composition to be assessed
        Returns
            (float) Average APE of all atoms
            (float) Average deviation of the APE of each atom from ideal (0)
        """

        # Compute the average atomic radius of the system
        elements, fractions = zip(*comp.element_composition.items())
        radii = self._data_source.get_elemental_properties(elements,
                                                           'MiracleRadius')
        mean_radius = PropertyStats.mean(radii, fractions)

        # Compute the APE for each cluster
        best_ape = [
            self.find_ideal_cluster_size(r / mean_radius)[1] for r in radii
        ]

        # Return the averages
        return PropertyStats.mean(best_ape, fractions), PropertyStats.mean(np.abs(best_ape), fractions)

    def compute_nearest_cluster_distance(self, comp):
        """Compute the distance between a composition and that the nearest
        efficiently-packed clusters.

        Measures the mean :math:`L_2` distance between the alloy composition
        and the :math:`k`-nearest clusters with Atomic Packing Efficiencies
        within the user-specified tolerance of 1. :math:`k` is any of the
        numbers defined in the "n_nearest" parameter of this class.

        If there are less than `k` efficient clusters in the system, we use
        the maximum distance betweeen any two compositions (1) for the
        unmatched neighbors.

        Args:
            comp (Composition): Composition of material to evaluate
        Return:
            [float] Average distances
        """

        # Get the most common elements
        elems, _ = zip(*sorted(comp.element_composition.items(),
                                   key=lambda x: x[1], reverse=True))

        # Get the cluster lookup tool using the most common elements
        cluster_lookup = self.create_cluster_lookup_tool(
            elems[:self.max_types]
        )

        # Compute the composition vector
        comp_vec = self._el_frac.featurize(comp)

        # Compute the distances
        means = []
        for k in self.n_nearest:
            # Get the nearest clusters
            if cluster_lookup is None:
                dists = (np.array([]),)
                to_lookup = 0
            else:
                to_lookup = min(cluster_lookup._fit_X.shape[0], k)
                dists, _ = cluster_lookup.kneighbors([comp_vec], to_lookup)

            # Pad the list with 1's
            dists = dists[0].tolist() + [1]*(k - to_lookup)

            # Compute the average
            means.append(np.mean(dists))

        return means

    def create_cluster_lookup_tool(self, elements):
        """
        Get the compositions of efficiently-packed clusters in a certain system
        of elements

        Args:
            elements ([Element]): Elements in system
        Return:
            (NearNeighbors): Tool to find nearby clusters in this system.
                None if there are no efficiently-packed clusters for this
                combination of elements
        """
        elements = list(set(elements))
        return self._create_cluster_lookup_tool(tuple(sorted(elements)))

    @lru_cache()
    def _create_cluster_lookup_tool(self, elements):
        """
        Cached version of `create_cluster_lookup_tool`. Assumes that the
        elements are passed as sorted tuple with no duplicates

        Args:
            elements ([Element]): Elements in system
        Return:
            (NearNeighbors): Tool to find nearby clusters in this system. If
            there are no clusters, this class returns None
        """

        # Get the radii
        radii = self._data_source.get_elemental_properties(elements,
                                                           "MiracleRadius")

        # Get the maximum and minimum cluster sizes
        max_size = self.find_ideal_cluster_size(max(radii) / min(radii))[0]
        min_size = self.find_ideal_cluster_size(min(radii) / max(radii))[0]

        # Prepare a list to hold all possible clusters
        eff_clusters = []

        # Loop through all possible neighbor shells
        for size in range(min_size, max_size + 1):
            # Get the ideal radius ratio for a cluster of this size
            ideal_ratio = self.get_ideal_radius_ratio(size)

            # Get the mean radii and compositions of all possible
            #  combinations of elements in the neighbor shell
            s_radii = itertools.combinations_with_replacement(radii, size)
            s_elems = itertools.combinations_with_replacement(elements, size)

            #  Put the results in arrays for fast indexing
            mean_radii = np.array(list(s_radii)).mean(axis=1)
            s_elems = np.array(list(s_elems))

            # For each type of central atom, determine which have an APE
            #  within `self.threshold` of 1
            for center_radius, center_elem in zip(radii, elements):
                # Compute the APE of each cluster
                ape = 1 - np.divide(ideal_ratio, np.divide(center_radius,
                                                           mean_radii))

                # Get those which are within the threshold of 0
                #  and add their composition to the list of OK elements
                for hit in s_elems[np.abs(ape) < self.threshold]:
                    eff_clusters.append([center_elem] + hit.tolist())

        # Compute the composition vectors for all of the efficient clusters
        comps = np.zeros((len(eff_clusters), self._n_elems))
        for i, elems in enumerate(eff_clusters):
            for elem in elems:
                comps[i, elem.Z - 1] += 1
        comps = np.divide(comps, comps.sum(axis=1)[:, None])

        # Return tool to quickly determine distance from efficient clusters
        #  NearNeighbors requires at least 1 entry, so we return None if
        #   there are no nearby clusters
        return NearestNeighbors().fit(comps) if len(comps) > 0 else None

    def find_ideal_cluster_size(self, radius_ratio):
        """
        Get the optimal cluster size for a certain radius ratio

        Finds the number of nearest neighbors :math:`n` that minimizes
        :math:`|1 - rp(n)/r|`, where :math:`rp(n)` is the ideal radius
        ratio for a certain :math:`n` and :math:`r` is the actual ratio.

        Args:
            radius_ratio (float): :math:`r / r_{neighbor}`
        Returns:
            (int) number of neighboring atoms for that will be the most
            efficiently packed.
            (float) Optimal APE
        """

        # Loop through cluster sizes from 3 to 24
        best_ape = np.inf
        best_n = None
        for n in range(3, 25):
            # Compute APE, check if it is the best
            ape = 1 - self.get_ideal_radius_ratio(n) / radius_ratio
            if abs(ape) < abs(best_ape):
                best_ape = ape
                best_n = n

            # If the APE is negative, this is either the best APE or
            #  We have already passed it
            if ape < 0:
                return best_n, best_ape

        return best_n, best_ape

    def get_ideal_radius_ratio(self, n_neighbors):
        """Compute the idea ratio between the central atom and neighboring
        atoms for a neighbor with a certain number of nearest neighbors.

        Based on work by `Miracle, Lord, and Ranganathan
        <https://www.jstage.jst.go.jp/article/matertrans/47/7/47_7_1737/_article/-char/en>`_.

        Args:
            n_neighbors (int): Number of atoms in 1st NN shell
        Return:
            (float) ideal radius ratio :math:`r / r_{neighbor}`
        """

        # NN must be in [3, 24]
        n = max(3, min(n_neighbors, 24))

        return self.ideal_ratio[n]
Beispiel #12
0
 def feature_labels(self):
     # Since we have more features than just element fractions, append 'fraction' to element symbols for clarity
     element_fraction_features = [e + " fraction" for e in ElementFraction().feature_labels()]
     valence_orbital_features = ValenceOrbital().feature_labels()
     return element_fraction_features+self._element_property_feature_labels+valence_orbital_features