Source code for nifty7.operators.outer_product_operator

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# Copyright(C) 2013-2020 Max-Planck-Society
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# NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik.

import numpy as np

from ..domain_tuple import DomainTuple
from ..field import Field
from .linear_operator import LinearOperator


[docs]class OuterProduct(LinearOperator): """Performs the point-wise outer product of two fields. Parameters --------- domain: DomainTuple, the domain of the input field field: Field --------- """ def __init__(self, domain, field): self._domain = DomainTuple.make(domain) self._field = field self._target = DomainTuple.make( tuple(sub_d for sub_d in field.domain._dom + self._domain._dom)) self._capability = self.TIMES | self.ADJOINT_TIMES
[docs] def apply(self, x, mode): self._check_input(x, mode) if mode == self.TIMES: return Field( self._target, np.multiply.outer( self._field.val, x.val)) axes = len(self._field.shape) return Field( self._domain, np.tensordot(self._field.val, x.val, axes))