Source code for nifty7.operators.mask_operator

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# Copyright(C) 2013-2019 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 ..domains.unstructured_domain import UnstructuredDomain
from ..field import Field
from .linear_operator import LinearOperator


[docs]class MaskOperator(LinearOperator): """Implementation of a mask response Takes a field, applies flags and returns the values of the field in a :class:`UnstructuredDomain`. Parameters ---------- flags : Field Is converted to boolean. Where True, the input field is flagged. """ def __init__(self, flags): if not isinstance(flags, Field): raise TypeError self._domain = DomainTuple.make(flags.domain) self._flags = np.logical_not(flags.val) self._target = DomainTuple.make(UnstructuredDomain(self._flags.sum())) self._capability = self.TIMES | self.ADJOINT_TIMES
[docs] def apply(self, x, mode): self._check_input(x, mode) x = x.val if mode == self.TIMES: res = x[self._flags] return Field(self.target, res) res = np.empty(self.domain.shape, x.dtype) res[self._flags] = x res[~self._flags] = 0 return Field(self.domain, res)