domain_tuple.py 6.21 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/>.
#
14
# Copyright(C) 2013-2019 Max-Planck-Society
Martin Reinecke's avatar
Martin Reinecke committed
15
#
16
# NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik.
Martin Reinecke's avatar
Martin Reinecke committed
17

Martin Reinecke's avatar
Martin Reinecke committed
18
from functools import reduce
Philipp Arras's avatar
Philipp Arras committed
19
from . import utilities
Martin Reinecke's avatar
Martin Reinecke committed
20
from .domains.domain import Domain
Martin Reinecke's avatar
Martin Reinecke committed
21

22 23
import numpy as np

Martin Reinecke's avatar
Martin Reinecke committed
24

Martin Reinecke's avatar
Martin Reinecke committed
25
class DomainTuple(object):
Martin Reinecke's avatar
Martin Reinecke committed
26 27
    """Ordered sequence of Domain objects.

28 29
    This class holds a tuple of :class:`Domain` objects, which together form
    the space on which a :class:`Field` is defined.
Reimar H Leike's avatar
Reimar H Leike committed
30 31
    This corresponds to a tensor product of the corresponding vector
    fields.
Martin Reinecke's avatar
Martin Reinecke committed
32 33 34 35 36 37 38

    Notes
    -----

    DomainTuples should never be created using the constructor, but rather
    via the factory function :attr:`make`!
    """
39
    _tupleCache = {}
Martin Reinecke's avatar
tweaks  
Martin Reinecke committed
40
    _scalarDomain = None
41

Martin Reinecke's avatar
step 1  
Martin Reinecke committed
42 43 44
    def __init__(self, domain, _callingfrommake=False):
        if not _callingfrommake:
            raise NotImplementedError
Martin Reinecke's avatar
Martin Reinecke committed
45 46
        self._dom = self._parse_domain(domain)
        self._axtuple = self._get_axes_tuple()
Martin Reinecke's avatar
Martin Reinecke committed
47 48 49
        self._shape = reduce(lambda x, y: x+y, (sp.shape for sp in self._dom),
                             ())
        self._size = reduce(lambda x, y: x*y, self._shape, 1)
Martin Reinecke's avatar
Martin Reinecke committed
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
Martin Reinecke's avatar
Martin Reinecke committed
58
        return tuple(res)
Martin Reinecke's avatar
Martin Reinecke committed
59 60 61

    @staticmethod
    def make(domain):
Martin Reinecke's avatar
Martin Reinecke committed
62 63 64 65 66 67 68 69 70 71 72 73
        """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
74 75
        if isinstance(domain, DomainTuple):
            return domain
76 77 78 79
        domain = DomainTuple._parse_domain(domain)
        obj = DomainTuple._tupleCache.get(domain)
        if obj is not None:
            return obj
Martin Reinecke's avatar
step 1  
Martin Reinecke committed
80
        obj = DomainTuple(domain, _callingfrommake=True)
81 82
        DomainTuple._tupleCache[domain] = obj
        return obj
Martin Reinecke's avatar
Martin Reinecke committed
83 84 85 86 87

    @staticmethod
    def _parse_domain(domain):
        if domain is None:
            return ()
Martin Reinecke's avatar
Martin Reinecke committed
88
        if isinstance(domain, Domain):
Martin Reinecke's avatar
Martin Reinecke committed
89 90 91 92 93
            return (domain,)

        if not isinstance(domain, tuple):
            domain = tuple(domain)
        for d in domain:
Martin Reinecke's avatar
Martin Reinecke committed
94
            if not isinstance(d, Domain):
Martin Reinecke's avatar
Martin Reinecke committed
95 96
                raise TypeError(
                    "Given object contains something that is not an "
Martin Reinecke's avatar
Martin Reinecke committed
97
                    "instance of Domain class.")
Martin Reinecke's avatar
Martin Reinecke committed
98 99 100 101 102 103 104
        return domain

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

    @property
    def shape(self):
Martin Reinecke's avatar
Martin Reinecke committed
105 106 107
        """tuple of int: number of pixels along each axis

        The shape of the array-like object required to store information
Philipp Arras's avatar
Philipp Arras committed
108
        defined on the DomainTuple.
Martin Reinecke's avatar
Martin Reinecke committed
109
        """
Martin Reinecke's avatar
Martin Reinecke committed
110 111 112
        return self._shape

    @property
Martin Reinecke's avatar
Martin Reinecke committed
113
    def size(self):
Martin Reinecke's avatar
Martin Reinecke committed
114 115 116 117
        """int : total number of pixels.

        Equivalent to the products over all entries in the object's shape.
        """
Martin Reinecke's avatar
Martin Reinecke committed
118
        return self._size
Martin Reinecke's avatar
Martin Reinecke committed
119

120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147
    def scalar_weight(self, spaces=None):
        """Returns the uniform volume element for a sub-domain of `self`.

        Parameters
        ----------
        spaces : int, tuple of int or None
            Indices of the sub-domains to be considered.
            If `None`, the entire domain is used.

        Returns
        -------
        float or None
            If the requested sub-domain has a uniform volume element, it is
            returned. Otherwise, `None` is returned.
        """
        if np.isscalar(spaces):
            return self._dom[spaces].scalar_dvol

        if spaces is None:
            spaces = range(len(self._dom))
        res = 1.
        for i in spaces:
            tmp = self._dom[i].scalar_dvol
            if tmp is None:
                return None
            res *= tmp
        return res

148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166
    def total_volume(self, spaces=None):
        """Returns the total volume of `self` or of a subspace of it.

        Parameters
        ----------
        spaces : int, tuple of int or None
            Indices of the sub-domains of the domain to be considered.
            If `None`, the total volume of the whole domain is returned.

        Returns
        -------
        float
            the total volume of the requested (sub-)domain.
        """
        if np.isscalar(spaces):
            return self._dom[spaces].total_volume

        if spaces is None:
            spaces = range(len(self._dom))
167
        res = 1.
168 169
        for i in spaces:
            res *= self._dom[i].total_volume
170 171
        return res

Martin Reinecke's avatar
Martin Reinecke committed
172 173
    @property
    def axes(self):
Martin Reinecke's avatar
Martin Reinecke committed
174
        """tuple of tuple of int : axis indices of the underlying domains"""
Martin Reinecke's avatar
Martin Reinecke committed
175 176 177 178 179 180 181 182 183
        return self._axtuple

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

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

    def __eq__(self, x):
Martin Reinecke's avatar
Martin Reinecke committed
184
        return (self is x) or (self._dom == x._dom)
Martin Reinecke's avatar
Martin Reinecke committed
185 186

    def __ne__(self, x):
Martin Reinecke's avatar
Martin Reinecke committed
187
        return not self.__eq__(x)
188 189

    def __str__(self):
Martin Reinecke's avatar
Martin Reinecke committed
190 191
        return ("DomainTuple, len: {}\n".format(len(self)) +
                "\n".join(str(i) for i in self))
Martin Reinecke's avatar
tweaks  
Martin Reinecke committed
192

193 194 195
    def __reduce__(self):
        return (_unpickleDomainTuple, (self._dom,))

Martin Reinecke's avatar
tweaks  
Martin Reinecke committed
196 197 198 199 200
    @staticmethod
    def scalar_domain():
        if DomainTuple._scalarDomain is None:
            DomainTuple._scalarDomain = DomainTuple.make(())
        return DomainTuple._scalarDomain
201 202 203 204

    def __repr__(self):
        subs = "\n".join(sub.__repr__() for sub in self._dom)
        return "DomainTuple:\n"+utilities.indent(subs)
205 206 207 208


def _unpickleDomainTuple(*args):
    return DomainTuple.make(*args)