operator_adapter.py

# 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 <http://www.gnu.org/licenses/>.
#
# Copyright(C) 2013-2018 Max-Planck-Society
#
# NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik
# and financially supported by the Studienstiftung des deutschen Volkes.

from .linear_operator import LinearOperator
import numpy as np


class OperatorAdapter(LinearOperator):
    """Class representing the inverse and/or adjoint of another operator."""

    def __init__(self, op, mode):
        super(OperatorAdapter, self).__init__()
        self._op = op
        self._mode = int(mode)
        if self._mode < 1 or self._mode > 3:
            raise ValueError("invalid mode")

    @property
    def domain(self):
        return self._op._dom(1 << self._mode)

    @property
    def target(self):
        return self._op._tgt(1 << self._mode)

    @property
    def capability(self):
        return self._capTable[self._mode][self._op.capability]

    def _flip_modes(self, mode):
        newmode = mode ^ self._mode
        return self._op if newmode == 0 else OperatorAdapter(self._op, newmode)

    def apply(self, x, mode):
        return self._op.apply(x, self._modeTable[self._mode][self._ilog[mode]])

    def draw_sample(self, dtype=np.float64):
        if self._mode & self.INVERSE_BIT:
            return self._op.inverse_draw_sample(dtype)
        return self._op.draw_sample(dtype)

    def inverse_draw_sample(self, dtype=np.float64):
        if self._mode & self.INVERSE_BIT:
            return self._op.draw_sample(dtype)
        return self._op.inverse_draw_sample(dtype)