# Source code for pymatgen.electronic_structure.cohp

    # coding: utf-8
    # Copyright (c) Pymatgen Development Team.
    # Distributed under the terms of the MIT License.

    """
    This module defines classes to represent crystal orbital Hamilton
    populations (COHP) and integrated COHP (ICOHP), but can also be used
    for crystal orbital overlap populations (COOP).
    """

    import warnings
    import re
    import sys

    import numpy as np

    from monty.json import MSONable

    from pymatgen.electronic_structure.core import Spin, Orbital
    from pymatgen.core.sites import PeriodicSite
    from pymatgen.core.structure import Structure
    from pymatgen.io.lmto import LMTOCopl
    from pymatgen.io.lobster import Cohpcar
    from pymatgen.util.num import round_to_sigfigs
    from pymatgen.util.coord import get_linear_interpolated_value

    __author__ = "Marco Esters, Janine George"
    __copyright__ = "Copyright 2017, The Materials Project"
    __version__ = "0.2"
    __maintainer__ = "Marco Esters, Janine George"
    __email__ = "esters@uoregon.edu, janine.george@uclouvain.be"
    __date__ = "Dec 13, 2017"

    class Cohp(MSONable):
        """
        Basic COHP object.
        """

        def __init__(self, efermi, energies, cohp, are_coops=False, icohp=None):
            """
            Args:
                are_coops: Indicates whether this object describes COHPs or COOPs.
                efermi: Fermi energy.
                energies: A sequence of energies.
                cohp ({Spin: np.array}): representing the COHP for each spin.
                icohp ({Spin: np.array}): representing the ICOHP for each spin.
            """
            self.are_coops = are_coops
            self.efermi = efermi
            self.energies = np.array(energies)
            self.cohp = cohp
            self.icohp = icohp

        def __add__(self, other):
            """
            Adds two COHP together. Checks that energy scales are the same.
            Otherwise, it raises a ValueError. It also adds ICOHP if present.
            If ICOHP is only present in one object, it displays a warning and
            will not add ICOHP.

            Args:
                other: Another COHP object.

            Returns:
                Sum of the two COHPs as a COHP object.
            """
            if not all(np.equal(self.energies, other.energies)):
                raise ValueError("Energies of both COHP are not compatible.")
            populations = {spin: self.populations[spin] + other.populations[spin]
                           for spin in self.cohp}
            if self.icohp is not None and other.icohp is not None:
                int_pop = {spin: self.icohp[spin] + other.icohp[spin]
                           for spin in self.icohp}
            else:
                if self.icohp is not None or other.icohp is not None:
                    warnings.warn("One of the COHP objects does not contain "
                                  "ICOHPs. Setting ICOHP to None.")
                int_pop = None
            return Cohp(self.efermi, self.energies, populations, icohp=int_pop)

        def __repr__(self):
            return self.__str__()

        def __str__(self):
            """
            Returns a string that can be easily plotted (e.g. using gnuplot).
            """
            cohpstring = "COOP" if self.are_coops else "COHP"
            header = ["Energy", cohpstring + "Up"]
            data = [self.energies, self.cohp[Spin.up]]
            if Spin.down in self.cohp:
                header.append(cohpstring + "Down")
                data.append(self.cohp[Spin.down])
            if self.icohp:
                header.append("I" + cohpstring + "Up")
                data.append(self.icohp[Spin.up])
                if Spin.down in self.cohp:
                    header.append("I" + cohpstring + "Down")
                    data.append(self.icohp[Spin.down])
            formatheader = "#" + " ".join(["{:15s}" for __ in header])
            formatdata = " ".join(["{:.5f}" for __ in header])
            stringarray = [formatheader.format(*header)]
            for i, __ in enumerate(self.energies):
                stringarray.append(formatdata.format(*[d[i] for d in data]))
            return "\n".join(stringarray)

        def as_dict(self):
            """
            Json-serializable dict representation of COHP.
            """
            d = {"@module": self.__class__.__module__,
                 "@class": self.__class__.__name__,
                 "are_coops": self.are_coops,
                 "efermi": self.efermi,
                 "energies": self.energies.tolist(),
                 "COHP": {str(spin): pops.tolist()
                          for spin, pops in self.cohp.items()}}
            if self.icohp:
                d["ICOHP"] = {str(spin): pops.tolist()
                              for spin, pops in self.icohp.items()}
            return d

        def get_cohp(self, spin=None, integrated=False):
            """
            Returns the COHP or ICOHP for a particular spin.

            Args:
                spin: Spin. Can be parsed as spin object, integer (-1/1)
                    or str ("up"/"down")
                integrated: Return COHP (False) or ICOHP (True)

            Returns:
                Returns the CHOP or ICOHP for the input spin. If Spin is
                None and both spins are present, both spins will be returned
                as a dictionary.
            """
            if not integrated:
                populations = self.cohp
            else:
                populations = self.icohp

            if populations is None:
                return None
            if spin is None:
                return populations
            if isinstance(spin, int):
                spin = Spin(spin)
            elif isinstance(spin, str):
                s = {"up": 1, "down": -1}[spin.lower()]
                spin = Spin(s)
            return {spin: populations[spin]}

        def get_icohp(self, spin=None):
            """
            Convenient alternative to get the ICOHP for a particular spin.
            """
            return self.get_cohp(spin=spin, integrated=True)

        def get_interpolated_value(self, energy, integrated=False):
            """
            Returns the COHP for a particular energy.

            Args:
                energy: Energy to return the COHP value for.
            """
            inter = {}
            for spin in self.cohp:
                if not integrated:
                    inter[spin] = get_linear_interpolated_value(self.energies,
                                                                self.cohp[spin],
                                                                energy)
                elif self.icohp is not None:
                    inter[spin] = get_linear_interpolated_value(self.energies,
                                                                self.icohp[spin],
                                                                energy)
                else:
                    raise ValueError("ICOHP is empty.")
            return inter

        def has_antibnd_states_below_efermi(self, spin=None, limit=0.01):
            """
            Returns dict indicating if there are antibonding states below the Fermi level depending on the spin
                spin: Spin
                limit: -COHP smaller -limit will be considered.

            """
            warnings.warn("This method has not been tested on many examples. Check the parameter limit, pls!")

            populations = self.cohp
            number_energies_below_efermi = len([x for x in self.energies if x <= self.efermi])

            if populations is None:
                return None
            if spin is None:
                dict_to_return = {}
                for sp, cohpvalues in populations.items():
                    if (max(cohpvalues[0:number_energies_below_efermi])) > limit:
                        dict_to_return[sp] = True
                    else:
                        dict_to_return[sp] = False
            else:
                dict_to_return = {}
                if isinstance(spin, int):
                    spin = Spin(spin)
                elif isinstance(spin, str):
                    s = {"up": 1, "down": -1}[spin.lower()]
                    spin = Spin(s)
                if (max(populations[spin][0:number_energies_below_efermi])) > limit:
                    dict_to_return[spin] = True
                else:
                    dict_to_return[spin] = False

            return dict_to_return

        @classmethod
        def from_dict(cls, d):
            """
            Returns a COHP object from a dict representation of the COHP.

            """
            if "ICOHP" in d:
                icohp = {Spin(int(key)): np.array(val)
                         for key, val in d["ICOHP"].items()}
            else:
                icohp = None
            return Cohp(d["efermi"], d["energies"],
                        {Spin(int(key)): np.array(val)
                         for key, val in d["COHP"].items()},
                        icohp=icohp, are_coops=d["are_coops"])

    class CompleteCohp(Cohp):
        """
        A wrapper class that defines an average COHP, and individual COHPs.

        .. attribute: are_coops

             Indicates whether the object is of COOPs or COHPs.

        .. attribute: efermi

             Fermi energy

        .. attribute: energies

             Sequence of energies

        .. attribute: structure

             Structure associated with the COHPs.

        .. attribute: cohp, icohp

             The average COHP/ICOHP.

        .. attribute: all_cohps

             A dict of COHPs for individual bonds of the form {label: COHP}

        .. attribute: orb_res_cohp

            Orbital-resolved COHPs.
        """

        def __init__(self, structure, avg_cohp, cohp_dict, bonds=None,
                     are_coops=False, orb_res_cohp=None):
            """
            Args:
                structure: Structure assosciated with this COHP.
                avg_cohp: The average cohp as a COHP object.
                cohps: A dict of COHP objects for individual bonds of the form
                    {label: COHP}
                bonds: A dict containing information on the bonds of the form
                    {label: {key: val}}. The key-val pair can be any information
                    the user wants to put in, but typically contains the sites,
                    the bond length, and the number of bonds. If nothing is
                    supplied, it will default to an empty dict.
                are_coops: indicates whether the Cohp objects are COHPs or COOPs.
                    Defauls to False for COHPs.
                orb_res_cohp: Orbital-resolved COHPs.
            """
            super().__init__(avg_cohp.efermi, avg_cohp.energies, avg_cohp.cohp,
                             are_coops=are_coops, icohp=avg_cohp.icohp)
            self.structure = structure
            self.are_coops = are_coops
            self.all_cohps = cohp_dict
            self.orb_res_cohp = orb_res_cohp
            if bonds is None:
                self.bonds = {label: {} for label in self.all_cohps.keys()}
            else:
                self.bonds = bonds

        def __str__(self):
            if self.are_coops:
                return "Complete COOPs for " + str(self.structure)
            return "Complete COHPs for " + str(self.structure)

        def as_dict(self):
            """
            Json-serializable dict representation of CompleteCohp.
            """
            d = {"@module": self.__class__.__module__,
                 "@class": self.__class__.__name__,
                 "are_coops": self.are_coops,
                 "efermi": self.efermi,
                 "structure": self.structure.as_dict(),
                 "energies": self.energies.tolist(),
                 "COHP": {"average": {str(spin): pops.tolist()
                                      for spin, pops in
                                      self.cohp.items()}}}

            if self.icohp is not None:
                d["ICOHP"] = {"average": {str(spin): pops.tolist()
                                          for spin, pops in
                                          self.icohp.items()}}

            for label in self.all_cohps.keys():
                d["COHP"].update({label: {str(spin): pops.tolist()
                                          for spin, pops in
                                          self.all_cohps[label].cohp.items()}})
                if self.all_cohps[label].icohp is not None:
                    if "ICOHP" not in d.keys():
                        d["ICOHP"] = {label: {str(spin): pops.tolist()
                                              for spin, pops in
                                              self.all_cohps[label].icohp.items()}}
                    else:
                        d["ICOHP"].update({label: {str(spin): pops.tolist()
                                                   for spin, pops in
                                                   self.all_cohps[label].icohp.items()}})
            if False in [bond_dict == {} for bond_dict in self.bonds.values()]:
                d["bonds"] = {bond: {"length": self.bonds[bond]["length"],
                                     "sites": [site.as_dict() for site
                                               in self.bonds[bond]["sites"]]}
                              for bond in self.bonds}
            if self.orb_res_cohp:
                orb_dict = {}
                for label in self.orb_res_cohp:
                    orb_dict[label] = {}
                    for orbs in self.orb_res_cohp[label]:
                        cohp = {str(spin): pops.tolist() for spin, pops in
                                self.orb_res_cohp[label][orbs]["COHP"].items()}
                        orb_dict[label][orbs] = {"COHP": cohp}
                        icohp = {str(spin): pops.tolist() for spin, pops in
                                 self.orb_res_cohp[label][orbs]["ICOHP"].items()}
                        orb_dict[label][orbs]["ICOHP"] = icohp
                        orbitals = [[orb[0], orb[1].name] for orb in
                                    self.orb_res_cohp[label][orbs]["orbitals"]]
                        orb_dict[label][orbs]["orbitals"] = orbitals
                d["orb_res_cohp"] = orb_dict

            return d

        def get_cohp_by_label(self, label):
            """
            Get specific COHP object.

            Args:
                label: string (for newer Lobster versions: a number)

            Returns:
                Returns the COHP object to simplify plotting
            """
            if label.lower() == "average":
                return Cohp(efermi=self.efermi, energies=self.energies,
                            cohp=self.cohp, are_coops=self.are_coops, icohp=self.icohp)
            return Cohp(efermi=self.efermi, energies=self.energies,
                        cohp=self.all_cohps[label].get_cohp(spin=None, integrated=False),
                        are_coops=self.are_coops,
                        icohp=self.all_cohps[label].get_icohp(spin=None))

        def get_summed_cohp_by_label_list(self, label_list, divisor=1):
            """
            Returns a COHP object that includes a summed COHP divided by divisor

            Args:
                label_list: list of labels for the COHP that should be included in the summed cohp
                divisor: float/int, the summed cohp will be divided by this divisor
            Returns:
                Returns a COHP object including a summed COHP
            """
            # check if cohps are spinpolarized or not
            first_cohpobject = self.get_cohp_by_label(label_list[0])
            summed_cohp = first_cohpobject.cohp.copy()
            summed_icohp = first_cohpobject.icohp.copy()
            for label in label_list[1:]:
                cohp_here = self.get_cohp_by_label(label)
                summed_cohp[Spin.up] = np.sum([summed_cohp[Spin.up], cohp_here.cohp[Spin.up]], axis=0)
                if Spin.down in summed_cohp:
                    summed_cohp[Spin.down] = np.sum([summed_cohp[Spin.down], cohp_here.cohp[Spin.down]], axis=0)
                summed_icohp[Spin.up] = np.sum([summed_icohp[Spin.up], cohp_here.icohp[Spin.up]], axis=0)
                if Spin.down in summed_icohp:
                    summed_icohp[Spin.down] = np.sum([summed_icohp[Spin.down], cohp_here.icohp[Spin.down]], axis=0)

            divided_cohp = {}
            divided_icohp = {}
            divided_cohp[Spin.up] = np.divide(summed_cohp[Spin.up], divisor)
            divided_icohp[Spin.up] = np.divide(summed_icohp[Spin.up], divisor)
            if Spin.down in summed_cohp:
                divided_cohp[Spin.down] = np.divide(summed_cohp[Spin.down], divisor)
                divided_icohp[Spin.down] = np.divide(summed_icohp[Spin.down], divisor)

            return Cohp(efermi=first_cohpobject.efermi, energies=first_cohpobject.energies, cohp=divided_cohp,
                        are_coops=first_cohpobject.are_coops,
                        icohp=divided_icohp)

        def get_summed_cohp_by_label_and_orbital_list(self, label_list, orbital_list, divisor=1):
            """
            Returns a COHP object that includes a summed COHP divided by divisor

            Args:
                label_list: list of labels for the COHP that should be included in the summed cohp
                orbital_list: list of orbitals for the COHPs that should be included in the summed cohp (same order as
                    label_list)
                divisor: float/int, the summed cohp will be divided by this divisor
            Returns:
                Returns a COHP object including a summed COHP
            """
            # check length of label_list and orbital_list:
            if not len(label_list) == len(orbital_list):
                raise ValueError("label_list and orbital_list don't have the same length!")
            # check if cohps are spinpolarized or not
            first_cohpobject = self.get_orbital_resolved_cohp(label_list[0], orbital_list[0])
            summed_cohp = first_cohpobject.cohp.copy()
            summed_icohp = first_cohpobject.icohp.copy()
            for ilabel, label in enumerate(label_list[1:], 1):
                cohp_here = self.get_orbital_resolved_cohp(label, orbital_list[ilabel])
                summed_cohp[Spin.up] = np.sum([summed_cohp[Spin.up], cohp_here.cohp.copy()[Spin.up]], axis=0)
                if Spin.down in summed_cohp:
                    summed_cohp[Spin.down] = np.sum([summed_cohp[Spin.down], cohp_here.cohp.copy()[Spin.down]], axis=0)
                summed_icohp[Spin.up] = np.sum([summed_icohp[Spin.up], cohp_here.icohp.copy()[Spin.up]], axis=0)
                if Spin.down in summed_icohp:
                    summed_icohp[Spin.down] = np.sum([summed_icohp[Spin.down], cohp_here.icohp.copy()[Spin.down]], axis=0)

            divided_cohp = {}
            divided_icohp = {}
            divided_cohp[Spin.up] = np.divide(summed_cohp[Spin.up], divisor)
            divided_icohp[Spin.up] = np.divide(summed_icohp[Spin.up], divisor)
            if Spin.down in summed_cohp:
                divided_cohp[Spin.down] = np.divide(summed_cohp[Spin.down], divisor)
                divided_icohp[Spin.down] = np.divide(summed_icohp[Spin.down], divisor)

            return Cohp(efermi=first_cohpobject.efermi, energies=first_cohpobject.energies, cohp=divided_cohp,
                        are_coops=first_cohpobject.are_coops,
                        icohp=divided_icohp)

        def get_orbital_resolved_cohp(self, label, orbitals):
            """
            Get orbital-resolved COHP.

            Args:
                label: bond label (Lobster: labels as in ICOHPLIST/ICOOPLIST.lobster).

                orbitals: The orbitals as a label, or list or tuple of the form
                    [(n1, orbital1), (n2, orbital2)]. Orbitals can either be str,
                    int, or Orbital.

            Returns:
                A Cohp object if CompleteCohp contains orbital-resolved cohp,
                or None if it doesn't.

            Note: It currently assumes that orbitals are str if they aren't the
                other valid types. This is not ideal, but the easiest way to
                avoid unicode issues between python 2 and python 3.
            """
            if self.orb_res_cohp is None:
                return None
            if isinstance(orbitals, (list, tuple)):
                cohp_orbs = [d["orbitals"] for d in
                             self.orb_res_cohp[label].values()]
                orbs = []
                for orbital in orbitals:
                    if isinstance(orbital[1], int):
                        orbs.append(tuple((orbital[0], Orbital(orbital[1]))))
                    elif isinstance(orbital[1], Orbital):
                        orbs.append(tuple((orbital[0], orbital[1])))
                    elif isinstance(orbital[1], str):
                        orbs.append(tuple((orbital[0], Orbital[orbital[1]])))
                    else:
                        raise TypeError("Orbital must be str, int, or Orbital.")
                orb_index = cohp_orbs.index(orbs)
                orb_label = list(self.orb_res_cohp[label].keys())[orb_index]
            elif isinstance(orbitals, str):
                orb_label = orbitals
            else:
                raise TypeError("Orbitals must be str, list, or tuple.")
            try:
                icohp = self.orb_res_cohp[label][orb_label]["ICOHP"]
            except KeyError:
                icohp = None
            return Cohp(self.efermi, self.energies,
                        self.orb_res_cohp[label][orb_label]["COHP"],
                        icohp=icohp, are_coops=self.are_coops)

        @classmethod
        def from_dict(cls, d):
            """
            Returns CompleteCohp object from dict representation.
            """
            cohp_dict = {}
            efermi = d["efermi"]
            energies = d["energies"]
            structure = Structure.from_dict(d["structure"])
            if "bonds" in d.keys():
                bonds = {bond: {"length": d["bonds"][bond]["length"],
                                "sites": tuple(PeriodicSite.from_dict(site)
                                               for site in d["bonds"][bond]["sites"])}
                         for bond in d["bonds"]}
            else:
                bonds = None
            for label in d["COHP"]:
                cohp = {Spin(int(spin)): np.array(d["COHP"][label][spin])
                        for spin in d["COHP"][label]}
                try:
                    icohp = {Spin(int(spin)): np.array(d["ICOHP"][label][spin])
                             for spin in d["ICOHP"][label]}
                except KeyError:
                    icohp = None
                if label == "average":
                    avg_cohp = Cohp(efermi, energies, cohp, icohp=icohp)
                else:
                    cohp_dict[label] = Cohp(efermi, energies, cohp, icohp=icohp)

            if "orb_res_cohp" in d.keys():
                orb_cohp = {}
                for label in d["orb_res_cohp"]:
                    orb_cohp[label] = {}
                    for orb in d["orb_res_cohp"][label]:
                        cohp = {Spin(int(s)): np.array(d["orb_res_cohp"][label][orb]["COHP"][s], dtype=float)
                                for s in d["orb_res_cohp"][label][orb]["COHP"]}
                        try:
                            icohp = {Spin(int(s)): np.array(d["orb_res_cohp"][label][orb]["ICOHP"][s], dtype=float)
                                     for s in d["orb_res_cohp"][label][orb]["ICOHP"]}
                        except KeyError:
                            icohp = None
                        orbitals = [tuple((int(o[0]), Orbital[o[1]])) for o in
                                    d["orb_res_cohp"][label][orb]["orbitals"]]
                        orb_cohp[label][orb] = {"COHP": cohp, "ICOHP": icohp,
                                                "orbitals": orbitals}
                    # If no total COHPs are present, calculate the total
                    # COHPs from the single-orbital populations. Total COHPs
                    # may not be present when the cohpgenerator keyword is used
                    # in LOBSTER versions 2.2.0 and earlier.
                    if label not in d["COHP"] or d["COHP"][label] is None:
                        cohp = {Spin.up: np.sum(np.array(
                            [orb_cohp[label][orb]["COHP"][Spin.up]
                             for orb in orb_cohp[label]]), axis=0)}
                        try:
                            cohp[Spin.down] = np.sum(np.array([orb_cohp[label][orb]["COHP"][Spin.down]
                                                               for orb in orb_cohp[label]]), axis=0)
                        except KeyError:
                            pass

                    orb_res_icohp = None in [orb_cohp[label][orb]["ICOHP"] for orb in orb_cohp[label]]
                    if (label not in d["ICOHP"] or d["ICOHP"][label] is None) and orb_res_icohp:
                        icohp = {Spin.up: np.sum(np.array([orb_cohp[label][orb]["ICOHP"][Spin.up]
                                                           for orb in orb_cohp[label]]), axis=0)}
                        try:
                            icohp[Spin.down] = np.sum(np.array([orb_cohp[label][orb]["ICOHP"][Spin.down]
                                                                for orb in orb_cohp[label]]), axis=0)
                        except KeyError:
                            pass
            else:
                orb_cohp = None

            if "average" not in d["COHP"].keys():
                # calculate average
                cohp = np.array([np.array(c)
                                 for c in d["COHP"].values()]).mean(axis=0)
                try:
                    icohp = np.array([np.array(c)
                                      for c in d["ICOHP"].values()]).mean(axis=0)
                except KeyError:
                    icohp = None
                avg_cohp = Cohp(efermi, energies, cohp, icohp=icohp)

            return CompleteCohp(structure, avg_cohp, cohp_dict, bonds=bonds,
                                are_coops=d["are_coops"], orb_res_cohp=orb_cohp)

        @classmethod
        def from_file(cls, fmt, filename=None,
                      structure_file=None, are_coops=False):
            """
            Creates a CompleteCohp object from an output file of a COHP
            calculation. Valid formats are either LMTO (for the Stuttgart
            LMTO-ASA code) or LOBSTER (for the LOBSTER code).

            Args:
                cohp_file: Name of the COHP output file. Defaults to COPL
                    for LMTO and COHPCAR.lobster/COOPCAR.lobster for LOBSTER.

                are_coops: Indicates whether the populations are COOPs or
                    COHPs. Defaults to False for COHPs.

                fmt: A string for the code that was used to calculate
                    the COHPs so that the output file can be handled
                    correctly. Can take the values "LMTO" or "LOBSTER".

                structure_file: Name of the file containing the structure.
                    If no file name is given, use CTRL for LMTO and POSCAR
                    for LOBSTER.

            Returns:
                A CompleteCohp object.
            """
            fmt = fmt.upper()
            if fmt == "LMTO":
                # LMTO COOPs and orbital-resolved COHP cannot be handled yet.
                are_coops = False
                orb_res_cohp = None
                if structure_file is None:
                    structure_file = "CTRL"
                if filename is None:
                    filename = "COPL"
                cohp_file = LMTOCopl(filename=filename, to_eV=True)
            elif fmt == "LOBSTER":
                if structure_file is None:
                    structure_file = "POSCAR"
                if filename is None:
                    filename = "COOPCAR.lobster" if are_coops \
                        else "COHPCAR.lobster"
                warnings.warn(
                    "The bond labels are currently consistent with ICOHPLIST.lobster/ICOOPLIST.lobster, not with "
                    "COHPCAR.lobster/COOPCAR.lobster. Please be aware!")
                cohp_file = Cohpcar(filename=filename, are_coops=are_coops)
                orb_res_cohp = cohp_file.orb_res_cohp
            else:
                raise ValueError("Unknown format %s. Valid formats are LMTO "
                                 "and LOBSTER." % fmt)

            structure = Structure.from_file(structure_file)
            efermi = cohp_file.efermi
            cohp_data = cohp_file.cohp_data
            energies = cohp_file.energies

            # Lobster shifts the energies so that the Fermi energy is at zero.
            # Shifting should be done by the plotter object though.

            spins = [Spin.up, Spin.down] if cohp_file.is_spin_polarized \
                else [Spin.up]
            if fmt == "LOBSTER":
                energies += efermi

            if orb_res_cohp is not None:
                # If no total COHPs are present, calculate the total
                # COHPs from the single-orbital populations. Total COHPs
                # may not be present when the cohpgenerator keyword is used
                # in LOBSTER versions 2.2.0 and earlier.
                # TODO: Test this more extensively
                for label in orb_res_cohp:
                    if cohp_file.cohp_data[label]["COHP"] is None:
                        # print(label)
                        cohp_data[label]["COHP"] = {
                            sp: np.sum([orb_res_cohp[label][orbs]["COHP"][sp] for orbs in orb_res_cohp[label]], axis=0)
                            for sp in spins}
                    if cohp_file.cohp_data[label]["ICOHP"] is None:
                        cohp_data[label]["ICOHP"] = \
                            {sp: np.sum([orb_res_cohp[label][orbs]["ICOHP"][sp]
                                         for orbs in orb_res_cohp[label]],
                                        axis=0) for sp in spins}

            if fmt == "LMTO":
                # Calculate the average COHP for the LMTO file to be
                # consistent with LOBSTER output.
                avg_data = {"COHP": {}, "ICOHP": {}}
                for i in avg_data:
                    for spin in spins:
                        rows = np.array([cohp_data[label][i][spin]
                                         for label in cohp_data])
                        avg = np.average(rows, axis=0)
                        # LMTO COHPs have 5 significant figures
                        avg_data[i].update({spin: np.array([round_to_sigfigs(a, 5)
                                                            for a in avg], dtype=float)})
                avg_cohp = Cohp(efermi, energies,
                                avg_data["COHP"],
                                icohp=avg_data["ICOHP"])
            else:
                avg_cohp = Cohp(efermi, energies,
                                cohp_data["average"]["COHP"],
                                icohp=cohp_data["average"]["COHP"],
                                are_coops=are_coops)
                del cohp_data["average"]

            cohp_dict = {label: Cohp(efermi, energies,
                                     cohp_data[label]["COHP"],
                                     icohp=cohp_data[label]["ICOHP"],
                                     are_coops=are_coops)
                         for label in cohp_data}

            bond_dict = {label: {"length": cohp_data[label]["length"],
                                 "sites": [structure.sites[site]
                                           for site in cohp_data[label]["sites"]]}
                         for label in cohp_data}

            return CompleteCohp(structure, avg_cohp, cohp_dict, bonds=bond_dict,
                                are_coops=are_coops, orb_res_cohp=orb_res_cohp)

    class IcohpValue(MSONable):
        """
        Class to store information on an ICOHP or ICOOP value

        .. attribute:: num_bonds
                number of bonds used for the average cohp (relevant for Lobster versions <3.0) (int)

        .. attribute:: are_coops
                Boolean to indicate whether ICOOP or not

        .. attribute:: icohp
                dict={Spin.up: icohpvalue for spin.up, Spin.down: icohpvalue for spin.down}

        .. attribute:: summed_icohp:
                sum of icohp/icoop of both spin channels

        """

        def __init__(self, label, atom1, atom2, length, translation, num, icohp, are_coops=False):
            """
            Args:
                label: label for the icohp
                atom1: str of atom that is contributing to the bond
                atom2: str of second atom that is contributing to the bond
                length: float of bond lengths
                translation: translation list, e.g. [0,0,0]
                num: integer describing how often the bond exists
                icohp: dict={Spin.up: icohpvalue for spin.up, Spin.down: icohpvalue for spin.down}
            """
            self._are_coops = are_coops
            self._label = label
            self._atom1 = atom1
            self._atom2 = atom2
            self._length = length
            self._translation = translation
            self._num = num
            self._icohp = icohp
            if Spin.down in self._icohp:
                self._is_spin_polarized = True
            else:
                self._is_spin_polarized = False

        def __str__(self):

            if not self._are_coops:
                if self._is_spin_polarized:
                    return ("ICOHP " + str(self._label) + " between " + str(self._atom1) + " and " + str(self._atom2) +
                            " (" + str(self._translation) + "): " + str(self._icohp[Spin.up]) + " eV (Spin up) and " +
                            str(self._icohp[Spin.down]) + " eV (Spin down)")
                return ("ICOHP " + str(self._label) + " between " + str(self._atom1) + " and " + str(self._atom2) +
                        " (" + str(self._translation) + "): " + str(self._icohp[Spin.up]) + " eV (Spin up)")
            if self._is_spin_polarized:
                return ("ICOOP " + str(self._label) + " between " + str(self._atom1) + " and " + str(self._atom2) +
                        " (" + str(self._translation) + "): " + str(self._icohp[Spin.up]) + " (Spin up) and " +
                        str(self._icohp[Spin.down]) + " (Spin down)")
            return ("ICOOP " + str(self._label) + " between " + str(self._atom1) + " and " + str(self._atom2) +
                    " (" + str(self._translation) + "): " + str(self._icohp[Spin.up]) + " (Spin up)")

        @property
        def num_bonds(self):
            """
            tells the number of bonds for which the ICOHP value is an average
            Returns:
                Int
            """
            return self._num

        @property
        def are_coops(self):
            """
            tells if ICOOPs or not
            Returns:
                Boolean
            """
            return self._are_coops

        @property
        def is_spin_polarized(self):
            """
            tells if spin polarized calculation or not
            Returns:
                Boolean

            """
            return self._is_spin_polarized

        def icohpvalue(self, spin=Spin.up):
            """
            Args:
                spin: Spin.up or Spin.down
            Returns:
                icohpvalue (float) corresponding to chosen spin
            """
            if not self.is_spin_polarized and spin == Spin.down:
                raise ValueError("The calculation was not performed with spin polarization")

            return self._icohp[spin]

        @property
        def icohp(self):
            """
            dict with icohps for spinup and spindown
            Return:
                dict={Spin.up: icohpvalue for spin.up, Spin.down: icohpvalue for spin.down}
            """
            return self._icohp

        @property
        def summed_icohp(self):
            """
            Adds ICOHPs of both spin channels for spin polarized compounds
            Returns:
                 icohp value in eV
            """
            if self._is_spin_polarized:
                sum_icohp = self._icohp[Spin.down] + self._icohp[Spin.up]
            else:
                sum_icohp = self._icohp[Spin.up]
            return sum_icohp

    class IcohpCollection(MSONable):
        """
        Class to store IcohpValues

        .. attribute:: are_coops
            Boolean to indicate whether ICOHPs or ICOOPs are stored

        .. attribute:: is_spin_polarized
            Boolean to indicate if the Lobster calculation was done spin polarized or not

        """

        def __init__(self, list_labels, list_atom1, list_atom2, list_length,
                     list_translation, list_num, list_icohp, is_spin_polarized, are_coops=False):
            """
            Args:
                is_spin_polarized: Boolean to indicate if the Lobster calculation was done spin polarized or not Boolean to
                    indicate if the Lobster calculation was done spin polarized or not
                are_coops: Boolean to indicate whether ICOHPs or ICOOPs are stored
                list_labels: list of labels for ICOHP/ICOOP values
                list_atom1: list of str of atomnames e.g. "O1"
                list_atom2: list of str of atomnames e.g. "O1"
                list_length: list of lengths of corresponding bonds in Angstrom
                list_translation: list of translation list, e.g. [0,0,0]
                list_num: list of equivalent bonds, usually 1 starting from Lobster 3.0.0
                list_icohp: list of dict={Spin.up: icohpvalue for spin.up, Spin.down: icohpvalue for spin.down}
            """
            self._are_coops = are_coops
            self._icohplist = {}
            self._is_spin_polarized = is_spin_polarized
            self._list_labels = list_labels
            self._list_atom1 = list_atom1
            self._list_atom2 = list_atom2
            self._list_length = list_length
            self._list_translation = list_translation
            self._list_num = list_num
            self._list_icohp = list_icohp

            for ilist, listel in enumerate(list_labels):
                self._icohplist[listel] = IcohpValue(listel, list_atom1[ilist], list_atom2[ilist], list_length[ilist],
                                                     list_translation[ilist], list_num[ilist], list_icohp[ilist])

        def __str__(self):
            joinstr = []
            for value in self._icohplist.values():
                joinstr.append(str(value))
            return "\n".join(joinstr)

        def get_icohp_by_label(self, label, summed_spin_channels=True, spin=Spin.up):
            """
            get an icohp value for a certain bond as indicated by the label (bond labels starting by "1" as in
            ICOHPLIST/ICOOPLIST)

            Args:
                label: label in str format (usually the bond number in Icohplist.lobster/Icooplist.lobster
                summed_spin_channels: Boolean to indicate whether the ICOHPs/ICOOPs of both spin channels should be summed
                spin: if summed_spin_channels is equal to False, this spin indicates which spin channel should be returned

            Returns:
                float describing ICOHP/ICOOP value
            """

            icohp_here = self._icohplist[label]
            if icohp_here._is_spin_polarized:
                if summed_spin_channels:
                    return icohp_here.summed_icohp
                return icohp_here.icohpvalue(spin)
            return icohp_here.icohpvalue(spin)

        def get_summed_icohp_by_label_list(self, label_list, divisor=1.0, summed_spin_channels=True, spin=Spin.up):
            """
            get the sum of several ICOHP values that are indicated by a list of labels (labels of the bonds are the same as
            in ICOHPLIST/ICOOPLIST)

            Args:
                label_list: list of labels of the ICOHPs/ICOOPs that should be summed
                divisor: is used to divide the sum
                summed_spin_channels: Boolean to indicate whether the ICOHPs/ICOOPs of both spin channels should be summed
                spin: if summed_spin_channels is equal to False, this spin indicates which spin channel should be returned

            Returns:
                 float that is a sum of all ICOHPs/ICOOPs as indicated with label_list
            """
            sum_icohp = 0
            for label in label_list:
                icohp_here = self._icohplist[label]
                if icohp_here.num_bonds != 1:
                    warnings.warn("One of the ICOHP values is an average over bonds. This is currently not considered.")
                # prints warning if num_bonds is not equal to 1
                if icohp_here._is_spin_polarized:
                    if summed_spin_channels:
                        sum_icohp = sum_icohp + icohp_here.summed_icohp
                    else:
                        sum_icohp = sum_icohp + icohp_here.icohpvalue(spin)
                else:
                    sum_icohp = sum_icohp + icohp_here.icohpvalue(spin)
            return sum_icohp / divisor

        def get_icohp_dict_by_bondlengths(self, minbondlength=0.0, maxbondlength=8.0):
            """
            get a dict of IcohpValues corresponding to certaind bond lengths
            Args:
                minbondlength: defines the minimum of the bond lengths of the bonds
                maxbondlength: defines the maximum of the bond lengths of the bonds
            Returns:
                 dict of IcohpValues, the keys correspond to the values from the initial list_labels
            """
            newicohp_dict = {}
            for value in self._icohplist.values():
                if value._length >= minbondlength and value._length <= maxbondlength:
                    newicohp_dict[value._label] = value
            return newicohp_dict

        def get_icohp_dict_of_site(self, site, minsummedicohp=None, maxsummedicohp=None, minbondlength=0.0,
                                   maxbondlength=8.0, only_bonds_to=None):
            """
            get a dict of IcohpValue for a certain site (indicated by integer)
            Args:
                site: integer describing the site of interest, order as in Icohplist.lobster/Icooplist.lobster, starts at 0
                minsummedicohp: float, minimal icohp/icoop of the bonds that are considered. It is the summed ICOHP value
                    from both spin channels for spin polarized cases
                maxsummedicohp: float, maximal icohp/icoop of the bonds that are considered. It is the summed ICOHP value
                    from both spin channels for spin polarized cases
                minbondlength: float, defines the minimum of the bond lengths of the bonds
                maxbondlength: float, defines the maximum of the bond lengths of the bonds
                only_bonds_to: list of strings describing the bonding partners that are allowed, e.g. ['O']
            Returns:
                 dict of IcohpValues, the keys correspond to the values from the initial list_labels
            """

            newicohp_dict = {}
            for key, value in self._icohplist.items():
                atomnumber1 = int(re.split(r'(\d+)', value._atom1)[1]) - 1
                atomnumber2 = int(re.split(r'(\d+)', value._atom2)[1]) - 1
                if site in (atomnumber1, atomnumber2):
                    # manipulate order of atoms so that searched one is always atom1
                    if site == atomnumber2:
                        save = value._atom1
                        value._atom1 = value._atom2
                        value._atom2 = save

                    if only_bonds_to is None:
                        second_test = True
                    else:
                        second_test = (re.split(r'(\d+)', value._atom2)[0] in only_bonds_to)
                    if value._length >= minbondlength and value._length <= maxbondlength and second_test:
                        if minsummedicohp is not None:
                            if value.summed_icohp >= minsummedicohp:
                                if maxsummedicohp is not None:
                                    if value.summed_icohp <= maxsummedicohp:
                                        newicohp_dict[key] = value
                                else:
                                    newicohp_dict[key] = value
                        else:
                            if maxsummedicohp is not None:
                                if value.summed_icohp <= maxsummedicohp:
                                    newicohp_dict[key] = value
                            else:
                                newicohp_dict[key] = value

            return newicohp_dict

        def extremum_icohpvalue(self, summed_spin_channels=True, spin=Spin.up):
            """
            get ICOHP/ICOOP of strongest bond
            Args:
                summed_spin_channels: Boolean to indicate whether the ICOHPs/ICOOPs of both spin channels should be summed

                spin: if summed_spin_channels is equal to False, this spin indicates which spin channel should be returned
            Returns:
                lowest ICOHP/largest ICOOP value (i.e. ICOHP/ICOOP value of strongest bond)
            """
            if not self._are_coops:
                extremum = sys.float_info.max
            else:
                extremum = -sys.float_info.max

            if not self._is_spin_polarized:
                if spin == Spin.down:
                    warnings.warn("This spin channel does not exist. I am switching to Spin.up")
                spin = Spin.up

            for value in self._icohplist.values():
                if not value.is_spin_polarized or not summed_spin_channels:
                    if not self._are_coops:
                        if value.icohpvalue(spin) < extremum:
                            extremum = value.icohpvalue(spin)
                            # print(extremum)
                    else:
                        if value.icohpvalue(spin) > extremum:
                            extremum = value.icohpvalue(spin)
                            # print(extremum)
                else:
                    if not self._are_coops:
                        if value.summed_icohp < extremum:
                            extremum = value.summed_icohp
                            # print(extremum)
                    else:
                        if value.summed_icohp > extremum:
                            extremum = value.summed_icohp
                            # print(extremum)
            return extremum

        @property
        def is_spin_polarized(self):
            """
            :return: Whether it is spin polarized.
            """
            return self._is_spin_polarized

        @property
        def are_coops(self):
            """
            :return: Whether this is coops.
            """
            return self._are_coops