domain_tuple.py 4.23 KB
Newer Older
Martin Reinecke's avatar
Martin Reinecke committed
1 2 3 4 5 6 7 8 9 10 11 12 13
# 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/>.
#
Martin Reinecke's avatar
Martin Reinecke committed
14
# Copyright(C) 2013-2018 Max-Planck-Society
Martin Reinecke's avatar
Martin Reinecke committed
15 16 17 18 19
#
# NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik
# and financially supported by the Studienstiftung des deutschen Volkes.

from functools import reduce
Martin Reinecke's avatar
Martin Reinecke committed
20
from .domains.domain import Domain
Martin Reinecke's avatar
Martin Reinecke committed
21

Martin Reinecke's avatar
Martin Reinecke committed
22

Martin Reinecke's avatar
Martin Reinecke committed
23
class DomainTuple(object):
Martin Reinecke's avatar
Martin Reinecke committed
24 25 26 27 28 29 30 31 32 33 34
    """Ordered sequence of Domain objects.

    This class holds a set of :class:`Domain` objects, which together form the
    space on which a :class:`Field` is defined.

    Notes
    -----

    DomainTuples should never be created using the constructor, but rather
    via the factory function :attr:`make`!
    """
35 36
    _tupleCache = {}

Martin Reinecke's avatar
Martin Reinecke committed
37 38 39 40 41
    def __init__(self, domain):
        self._dom = self._parse_domain(domain)
        self._axtuple = self._get_axes_tuple()
        shape_tuple = tuple(sp.shape for sp in self._dom)
        self._shape = reduce(lambda x, y: x + y, shape_tuple, ())
Martin Reinecke's avatar
Martin Reinecke committed
42
        self._size = reduce(lambda x, y: x * y, self._shape, 1)
43 44
        prod = 1
        for dom in self._dom:
Martin Reinecke's avatar
Martin Reinecke committed
45
            prod *= dom.size
Martin Reinecke's avatar
Martin Reinecke committed
46 47 48 49 50 51 52 53 54 55 56 57

    def _get_axes_tuple(self):
        i = 0
        res = [None]*len(self._dom)
        for idx, thing in enumerate(self._dom):
            nax = len(thing.shape)
            res[idx] = tuple(range(i, i+nax))
            i += nax
        return res

    @staticmethod
    def make(domain):
Martin Reinecke's avatar
Martin Reinecke committed
58 59 60 61 62 63 64 65 66 67 68 69
        """Returns a DomainTuple matching `domain`.

        This function checks whether a matching DomainTuple already exists.
        If yes, this object is returned, otherwise a new DomainTuple object
        is created and returned.

        Parameters
        ----------
        domain : Domain or tuple of Domain or DomainTuple
            The geometrical structure for which the DomainTuple shall be
            obtained.
        """
Martin Reinecke's avatar
Martin Reinecke committed
70 71
        if isinstance(domain, DomainTuple):
            return domain
72 73 74 75 76 77 78
        domain = DomainTuple._parse_domain(domain)
        obj = DomainTuple._tupleCache.get(domain)
        if obj is not None:
            return obj
        obj = DomainTuple(domain)
        DomainTuple._tupleCache[domain] = obj
        return obj
Martin Reinecke's avatar
Martin Reinecke committed
79 80 81 82 83

    @staticmethod
    def _parse_domain(domain):
        if domain is None:
            return ()
Martin Reinecke's avatar
Martin Reinecke committed
84
        if isinstance(domain, Domain):
Martin Reinecke's avatar
Martin Reinecke committed
85 86 87 88 89
            return (domain,)

        if not isinstance(domain, tuple):
            domain = tuple(domain)
        for d in domain:
Martin Reinecke's avatar
Martin Reinecke committed
90
            if not isinstance(d, Domain):
Martin Reinecke's avatar
Martin Reinecke committed
91 92
                raise TypeError(
                    "Given object contains something that is not an "
Martin Reinecke's avatar
Martin Reinecke committed
93
                    "instance of Domain class.")
Martin Reinecke's avatar
Martin Reinecke committed
94 95 96 97 98 99 100
        return domain

    def __getitem__(self, i):
        return self._dom[i]

    @property
    def shape(self):
Martin Reinecke's avatar
Martin Reinecke committed
101 102 103 104 105
        """tuple of int: number of pixels along each axis

        The shape of the array-like object required to store information
        living on the DomainTuple.
        """
Martin Reinecke's avatar
Martin Reinecke committed
106 107 108
        return self._shape

    @property
Martin Reinecke's avatar
Martin Reinecke committed
109
    def size(self):
Martin Reinecke's avatar
Martin Reinecke committed
110 111 112 113
        """int : total number of pixels.

        Equivalent to the products over all entries in the object's shape.
        """
Martin Reinecke's avatar
Martin Reinecke committed
114
        return self._size
Martin Reinecke's avatar
Martin Reinecke committed
115 116 117

    @property
    def axes(self):
Martin Reinecke's avatar
Martin Reinecke committed
118
        """tuple of tuple of int : shapes of the underlying domains"""
Martin Reinecke's avatar
Martin Reinecke committed
119 120 121 122 123 124 125 126 127 128
        return self._axtuple

    def __len__(self):
        return len(self._dom)

    def __hash__(self):
        return self._dom.__hash__()

    def __eq__(self, x):
        if not isinstance(x, DomainTuple):
129 130 131
            x = DomainTuple.make(x)
        if self is x:
            return True
Martin Reinecke's avatar
Martin Reinecke committed
132 133 134
        return self._dom == x._dom

    def __ne__(self, x):
Martin Reinecke's avatar
Martin Reinecke committed
135
        return not self.__eq__(x)
136 137

    def __str__(self):
Martin Reinecke's avatar
Martin Reinecke committed
138 139
        res = "DomainTuple, len: " + str(len(self))
        for i in self:
140 141
            res += "\n" + str(i)
        return res