Source code for nifty8.domains.hp_space
# 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) 2013-2019 Max-Planck-Society
#
# NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik.
import numpy as np
from .structured_domain import StructuredDomain
[docs]
class HPSpace(StructuredDomain):
"""Represents 2-sphere with HEALPix discretization.
Its harmonic partner domain is the
:class:`~nifty8.domains.lm_space.LMSpace`.
Parameters
----------
nside : int
The corresponding HEALPix Nside parameter. Must be a positive integer
and typically is a power of 2.
"""
_needed_for_hash = ["_nside"]
[docs]
def __init__(self, nside):
self._nside = int(nside)
if self._nside < 1:
raise ValueError("nside must be >=1.")
[docs]
def __repr__(self):
return "HPSpace(nside={})".format(self.nside)
@property
def harmonic(self):
return False
@property
def shape(self):
return (self.size,)
@property
def size(self):
return int(12 * self.nside * self.nside)
@property
def scalar_dvol(self):
return np.pi / (3*self._nside*self._nside)
@property
def nside(self):
"""int : HEALPix Nside parameter of this domain"""
return self._nside
[docs]
def get_default_codomain(self):
"""Returns a :class:`LMSpace` object, which is capable of storing a
fairly accurate representation of data residing on `self`
Returns
-------
LMSpace
The partner domain
Notes
-----
The `lmax` and `mmax` parameters of the returned :class:`LMSpace` are
set to `2*self.nside`.
"""
from ..domains.lm_space import LMSpace
return LMSpace(lmax=2*self.nside)
[docs]
def check_codomain(self, codomain):
"""Raises `TypeError` if `codomain` is not a matching partner domain
for `self`.
Notes
-----
This function only checks whether `codomain` is of type
:class:`LMSpace`.
"""
from ..domains.lm_space import LMSpace
if not isinstance(codomain, LMSpace):
raise TypeError("codomain must be a LMSpace.")