# This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . # # Copyright(C) 2013-2019 Max-Planck-Society # # NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik. from ..domain_tuple import DomainTuple from ..domains.unstructured_domain import UnstructuredDomain from ..field import Field from ..multi_domain import MultiDomain from ..multi_field import MultiField from .endomorphic_operator import EndomorphicOperator from .linear_operator import LinearOperator class VdotOperator(LinearOperator): """Operator computing the scalar product of its input with a given Field. Parameters ---------- field : Field or MultiField The field used to build the scalar product with the operator input """ def __init__(self, field): self._field = field self._domain = field.domain self._target = DomainTuple.scalar_domain() self._capability = self.TIMES | self.ADJOINT_TIMES def apply(self, x, mode): self._check_mode(mode) if mode == self.TIMES: return Field.scalar(self._field.vdot(x)) return self._field*x.local_data[()] class ConjugationOperator(EndomorphicOperator): """Operator computing the complex conjugate of its input. Parameters ---------- domain: Domain, tuple of domains or DomainTuple domain of the input field """ def __init__(self, domain): self._domain = DomainTuple.make(domain) self._capability = self._all_ops def apply(self, x, mode): self._check_input(x, mode) return x.conjugate() class Realizer(EndomorphicOperator): """Operator returning the real component of its input. Parameters ---------- domain: Domain, tuple of domains or DomainTuple domain of the input field """ def __init__(self, domain): self._domain = DomainTuple.make(domain) self._capability = self.TIMES | self.ADJOINT_TIMES def apply(self, x, mode): self._check_input(x, mode) return x.real class FieldAdapter(LinearOperator): """Operator for conversion between Fields and MultiFields. Parameters ---------- tgt : Domain, tuple of Domain, DomainTuple, dict or MultiDomain: If this is a Domain, tuple of Domain or DomainTuple, this will be the operator's target, and its domain will be a MultiDomain consisting of its domain with the supplied `name` If this is a dict or MultiDomain, everything except for `name` will be stripped out of it, and the result will be the operator's target. Its domain will then be the DomainTuple corresponding to the single entry in the operator's domain. name : String The relevant key of the MultiDomain. """ def __init__(self, tgt, name): from ..sugar import makeDomain tmp = makeDomain(tgt) if isinstance(tmp, DomainTuple): self._target = tmp self._domain = MultiDomain.make({name: tmp}) else: self._domain = tmp[name] self._target = MultiDomain.make({name: tmp[name]}) self._capability = self.TIMES | self.ADJOINT_TIMES def apply(self, x, mode): self._check_input(x, mode) if isinstance(x, MultiField): return x.values()[0] else: return MultiField(self._tgt(mode), (x,)) def __repr__(self): key = self.domain.keys()[0] return 'FieldAdapter: {}'.format(key) def ducktape(left, right, name): """Convenience function creating an operator that converts between a DomainTuple and a single-entry MultiDomain. Parameters ---------- left : None, Operator, or Domainoid Something describing the new operator's target domain. If `left` is an `Operator`, its domain is used as `left`. right : None, Operator, or Domainoid Something describing the new operator's input domain. If `right` is an `Operator`, its target is used as `right`. name : string The component of the `MultiDomain` that will be extracted/inserted Notes ----- - one of the involved domains must be a `DomainTuple`, the other a `MultiDomain`. - `left` and `right` must not be both `None`, but one of them can (and probably should) be `None`. In this case, the missing information is inferred. - the returned operator's domains are - a `DomainTuple` and - a `MultiDomain` with exactly one entry called `name` and the same `DomainTuple` Which of these is the domain and which is the target depends on the input. Returns ------- FieldAdapter : an adapter operator converting between the two (possibly partially inferred) domains. """ from ..sugar import makeDomain from .operator import Operator if left is None: # need to infer left from right if isinstance(right, Operator): right = right.target elif right is not None: right = makeDomain(right) if isinstance(right, MultiDomain): left = right[name] else: left = MultiDomain.make({name: right}) else: if isinstance(left, Operator): left = left.domain else: left = makeDomain(left) return FieldAdapter(left, name) class GeometryRemover(LinearOperator): """Operator which transforms between a structured and an unstructured domain. Parameters ---------- domain: Domain, tuple of Domain, or DomainTuple: the full input domain of the operator. space: int, optional The index of the subdomain on which the operator should act. If None, it acts on all spaces. Notes ----- The operator will convert every sub-domain of its input domain to an UnstructuredDomain with the same shape. No weighting by volume factors is carried out. """ def __init__(self, domain, space=None): self._domain = DomainTuple.make(domain) if space is not None: tgt = [dom for dom in self._domain] tgt[space] = UnstructuredDomain(self._domain[space].shape) else: tgt = [UnstructuredDomain(dom.shape) for dom in self._domain] self._target = DomainTuple.make(tgt) self._capability = self.TIMES | self.ADJOINT_TIMES def apply(self, x, mode): self._check_input(x, mode) return x.cast_domain(self._tgt(mode)) class NullOperator(LinearOperator): """Operator corresponding to a matrix of all zeros. Parameters ---------- domain : DomainTuple or MultiDomain input domain target : DomainTuple or MultiDomain output domain """ def __init__(self, domain, target): from ..sugar import makeDomain self._domain = makeDomain(domain) self._target = makeDomain(target) self._capability = self.TIMES | self.ADJOINT_TIMES @staticmethod def _nullfield(dom): if isinstance(dom, DomainTuple): return Field(dom, 0) else: return MultiField.full(dom, 0) def apply(self, x, mode): self._check_input(x, mode) return self._nullfield(self._tgt(mode))