Integrated real harmonic RGSpace representation deeply into NIFTy.

demos/wiener_filter_via_curvature.py

@@ -2,13 +2,14 @@ import numpy as np
 
 from nifty import RGSpace, PowerSpace, Field, FFTOperator, ComposedOperator,\
                   DiagonalOperator, ResponseOperator, plotting,\
-                  create_power_operator
+                  create_power_operator, nifty_configuration
 from nifty.library import WienerFilterCurvature
 
 
 if __name__ == "__main__":
 
-    distribution_strategy = 'not'
+    nifty_configuration['default_distribution_strategy'] = 'fftw'
+    nifty_configuration['harmonic_rg_base'] = 'real'
 
     # Setting up variable parameters
 
@@ -36,19 +37,17 @@ if __name__ == "__main__":
 
     signal_space = RGSpace([N_pixels, N_pixels], distances=L/N_pixels)
     harmonic_space = FFTOperator.get_default_codomain(signal_space)
-    fft = FFTOperator(harmonic_space, target=signal_space,
-                      domain_dtype=np.complex, target_dtype=np.float)
-    power_space = PowerSpace(harmonic_space,
-                             distribution_strategy=distribution_strategy)
+    fft = FFTOperator(harmonic_space, target=signal_space)
+    power_space = PowerSpace(harmonic_space)
 
     # Creating the mock data
-    S = create_power_operator(harmonic_space, power_spectrum=power_spectrum,
-                              distribution_strategy=distribution_strategy)
+    S = create_power_operator(harmonic_space, power_spectrum=power_spectrum)
 
-    mock_power = Field(power_space, val=power_spectrum,
-                       distribution_strategy=distribution_strategy)
+    mock_power = Field(power_space, val=power_spectrum)
     np.random.seed(43)
     mock_harmonic = mock_power.power_synthesize(real_signal=True)
+    if nifty_configuration['harmonic_rg_base'] == 'real':
+        mock_harmonic = mock_harmonic.real
     mock_signal = fft(mock_harmonic)
 
     R = ResponseOperator(signal_space, sigma=(response_sigma,))
@@ -74,9 +73,10 @@ if __name__ == "__main__":
 
     plotter = plotting.RG2DPlotter()
     plotter.path = 'mock_signal.html'
-    plotter(mock_signal)
+    plotter(mock_signal.real)
     plotter.path = 'data.html'
-    plotter(Field(signal_space,
-                  val=data.val.get_full_data().reshape(signal_space.shape)))
+    plotter(Field(
+                signal_space,
+                val=data.val.get_full_data().real.reshape(signal_space.shape)))
     plotter.path = 'map.html'
-    plotter(m_s)
+    plotter(m_s.real)

demos/wiener_filter_via_curvature_real.py

-import numpy as np
-
-from nifty import RGSpace, PowerSpace, Field, RealFFTOperator,\
-                  ComposedOperator, DiagonalOperator, ResponseOperator,\
-                  plotting, create_power_operator
-from nifty.library import WienerFilterCurvature
-
-
-if __name__ == "__main__":
-
-    distribution_strategy = 'not'
-
-    # Setting up variable parameters
-
-    # Typical distance over which the field is correlated
-    correlation_length = 0.05
-    # Variance of field in position space sqrt(<|s_x|^2>)
-    field_variance = 2.
-    # smoothing length of response (in same unit as L)
-    response_sigma = 0.01
-    # The signal to noise ratio
-    signal_to_noise = 0.7
-
-    # note that field_variance**2 = a*k_0/4. for this analytic form of power
-    # spectrum
-    def power_spectrum(k):
-        a = 4 * correlation_length * field_variance**2
-        return a / (1 + k * correlation_length) ** 4
-
-    # Setting up the geometry
-
-    # Total side-length of the domain
-    L = 2.
-    # Grid resolution (pixels per axis)
-    N_pixels = 512
-
-    signal_space = RGSpace([N_pixels, N_pixels], distances=L/N_pixels)
-    harmonic_space = RealFFTOperator.get_default_codomain(signal_space)
-    fft = RealFFTOperator(harmonic_space, target=signal_space)
-    power_space = PowerSpace(harmonic_space,
-                             distribution_strategy=distribution_strategy)
-
-    # Creating the mock data
-    S = create_power_operator(harmonic_space, power_spectrum=power_spectrum,
-                              distribution_strategy=distribution_strategy)
-
-    mock_power = Field(power_space, val=power_spectrum,
-                       distribution_strategy=distribution_strategy)
-    np.random.seed(43)
-    mock_harmonic = mock_power.power_synthesize(real_signal=True)
-    mock_harmonic = mock_harmonic.real + mock_harmonic.imag
-    mock_signal = fft(mock_harmonic)
-
-    R = ResponseOperator(signal_space, sigma=(response_sigma,))
-    data_domain = R.target[0]
-    R_harmonic = ComposedOperator([fft, R], default_spaces=[0, 0])
-
-    N = DiagonalOperator(data_domain,
-                         diagonal=mock_signal.var()/signal_to_noise,
-                         bare=True)
-    noise = Field.from_random(domain=data_domain,
-                              random_type='normal',
-                              std=mock_signal.std()/np.sqrt(signal_to_noise),
-                              mean=0)
-    data = R(mock_signal) + noise
-
-    # Wiener filter
-
-    j = R_harmonic.adjoint_times(N.inverse_times(data))
-    wiener_curvature = WienerFilterCurvature(S=S, N=N, R=R_harmonic)
-
-    m = wiener_curvature.inverse_times(j)
-    m_s = fft(m)
-
-    plotter = plotting.RG2DPlotter()
-    plotter.path = 'mock_signal.html'
-    plotter(mock_signal)
-    plotter.path = 'data.html'
-    plotter(Field(signal_space,
-                  val=data.val.get_full_data().reshape(signal_space.shape)))
-    plotter.path = 'map.html'
-    plotter(m_s)

nifty/config/nifty_config.py

@@ -70,11 +70,18 @@ variable_default_distribution_strategy = keepers.Variable(
                                          if z == 'fftw' else True),
                               genus='str')
 
+variable_harmonic_rg_base = keepers.Variable(
+                                'harmonic_rg_base',
+                                ['real', 'complex'],
+                                lambda z: z in ['real', 'complex'],
+                                genus='str')
+
 nifty_configuration = keepers.get_Configuration(
                  name='NIFTy',
                  variables=[variable_fft_module,
                             variable_default_field_dtype,
-                            variable_default_distribution_strategy],
+                            variable_default_distribution_strategy,
+                            variable_harmonic_rg_base],
                  file_name='NIFTy.conf',
                  search_paths=[os.path.expanduser('~') + "/.config/nifty/",
                                os.path.expanduser('~') + "/.config/",

nifty/field.py

@@ -19,7 +19,6 @@
 from __future__ import division
 
 import ast
-import itertools
 import numpy as np
 
 from keepers import Versionable,\

nifty/operators/fft_operator/__init__.py

@@ -18,4 +18,3 @@
 
 from transformations import *
 from .fft_operator import FFTOperator
-from .real_fft_operator import RealFFTOperator

nifty/operators/fft_operator/fft_operator.py

@@ -142,17 +142,11 @@ class FFTOperator(LinearOperator):
             backward_class, self.target[0], self.domain[0], module=module)
 
         # Store the dtype information
-        if domain_dtype is None:
-            self.logger.info("Setting domain_dtype to np.complex.")
-            self.domain_dtype = np.complex
-        else:
-            self.domain_dtype = np.dtype(domain_dtype)
+        self.domain_dtype = \
+            None if domain_dtype is None else np.dtype(domain_dtype)
 
-        if target_dtype is None:
-            self.logger.info("Setting target_dtype to np.complex.")
-            self.target_dtype = np.complex
-        else:
-            self.target_dtype = np.dtype(target_dtype)
+        self.target_dtype = \
+            None if target_dtype is None else np.dtype(target_dtype)
 
     def _times(self, x, spaces):
         spaces = utilities.cast_axis_to_tuple(spaces, len(x.domain))
@@ -172,8 +166,10 @@ class FFTOperator(LinearOperator):
             result_domain = list(x.domain)
             result_domain[spaces[0]] = self.target[0]
 
+        result_dtype = \
+            new_val.dtype if self.target_dtype is None else self.target_dtype
         result_field = x.copy_empty(domain=result_domain,
-                                    dtype=self.target_dtype)
+                                    dtype=result_dtype)
         result_field.set_val(new_val=new_val, copy=True)
 
         return result_field
@@ -196,8 +192,11 @@ class FFTOperator(LinearOperator):
             result_domain = list(x.domain)
             result_domain[spaces[0]] = self.domain[0]
 
+        result_dtype = \
+            new_val.dtype if self.domain_dtype is None else self.domain_dtype
+
         result_field = x.copy_empty(domain=result_domain,
-                                    dtype=self.domain_dtype)
+                                    dtype=result_dtype)
         result_field.set_val(new_val=new_val, copy=True)
 
         return result_field

nifty/operators/fft_operator/real_fft_operator.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) 2013-2017 Max-Planck-Society
-#
-# NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik
-# and financially supported by the Studienstiftung des deutschen Volkes.
-
-import numpy as np
-
-import nifty.nifty_utilities as utilities
-from nifty.spaces import RGSpace,\
-                         GLSpace,\
-                         HPSpace,\
-                         LMSpace
-
-from nifty.operators.linear_operator import LinearOperator
-from transformations import RGRGTransformation,\
-                            LMGLTransformation,\
-                            LMHPTransformation,\
-                            GLLMTransformation,\
-                            HPLMTransformation,\
-                            TransformationCache
-
-
-class RealFFTOperator(LinearOperator):
-    """Transforms between a pair of position and harmonic domains.
-
-    Built-in domain pairs are
-      - a harmonic and a non-harmonic RGSpace (with matching distances)
-      - a HPSpace and a LMSpace
-      - a GLSpace and a LMSpace
-    Within a domain pair, both orderings are possible.
-
-    The operator provides a "times" and an "adjoint_times" operation.
-    For a pair of RGSpaces, the "adjoint_times" operation is equivalent to
-    "inverse_times"; for the sphere-related domains this is not the case, since
-    the operator matrix is not square.
-
-    In contrast to the FFTOperator, RealFFTOperator accepts and returns
-    real-valued fields only. For the harmonic-space counterpart of a
-    real-valued field living on an RGSpace, the sum of real
-    and imaginary components is stored. Since the full complex field has
-    Hermitian symmetry, this is sufficient to reconstruct the full field
-    whenever needed (e.g. during the transform back to position space).
-
-    Parameters
-    ----------
-    domain: Space or single-element tuple of Spaces
-        The domain of the data that is input by "times" and output by
-        "adjoint_times".
-    target: Space or single-element tuple of Spaces (optional)
-        The domain of the data that is output by "times" and input by
-        "adjoint_times".
-        If omitted, a co-domain will be chosen automatically.
-        Whenever "domain" is an RGSpace, the codomain (and its parameters) are
-        uniquely determined.
-        For GLSpace, HPSpace, and LMSpace, a sensible (but not unique)
-        co-domain is chosen that should work satisfactorily in most situations,
-        but for full control, the user should explicitly specify a codomain.
-    module: String (optional)
-        Software module employed for carrying out the transform operations.
-        For RGSpace pairs this can be "scalar" or "mpi", where "scalar" is
-        always available (using pyfftw if available, else numpy.fft), and "mpi"
-        requires pyfftw and offers MPI parallelization.
-        For sphere-related domains, only "pyHealpix" is
-        available. If omitted, "fftw" is selected for RGSpaces if available,
-        else "numpy"; on the sphere the default is "pyHealpix".
-
-    Attributes
-    ----------
-    domain: Tuple of Spaces (with one entry)
-        The domain of the data that is input by "times" and output by
-        "adjoint_times".
-    target: Tuple of Spaces (with one entry)
-        The domain of the data that is output by "times" and input by
-        "adjoint_times".
-    unitary: bool
-        Returns True if the operator is unitary (currently only the case if
-        the domain and codomain are RGSpaces), else False.
-
-    Raises
-    ------
-    ValueError:
-        if "domain" or "target" are not of the proper type.
-
-    """
-    default_codomain_dictionary = {RGSpace: RGSpace,
-                                   HPSpace: LMSpace,
-                                   GLSpace: LMSpace,
-                                   LMSpace: GLSpace,
-                                   }
-
-    transformation_dictionary = {(RGSpace, RGSpace): RGRGTransformation,
-                                 (HPSpace, LMSpace): HPLMTransformation,
-                                 (GLSpace, LMSpace): GLLMTransformation,
-                                 (LMSpace, HPSpace): LMHPTransformation,
-                                 (LMSpace, GLSpace): LMGLTransformation
-                                 }
-
-    def __init__(self, domain, target=None, module=None,
-                 default_spaces=None):
-        super(RealFFTOperator, self).__init__(default_spaces)
-
-        # Initialize domain and target
-        self._domain = self._parse_domain(domain)
-        if len(self.domain) != 1:
-            raise ValueError("TransformationOperator accepts only exactly one "
-                             "space as input domain.")
-
-        if target is None:
-            target = (self.get_default_codomain(self.domain[0]), )
-        self._target = self._parse_domain(target)
-        if len(self.target) != 1:
-            raise ValueError("TransformationOperator accepts only exactly one "
-                             "space as output target.")
-
-        # Create transformation instances
-        forward_class = self.transformation_dictionary[
-                (self.domain[0].__class__, self.target[0].__class__)]
-        backward_class = self.transformation_dictionary[
-                (self.target[0].__class__, self.domain[0].__class__)]
-
-        self._forward_transformation = TransformationCache.create(
-            forward_class, self.domain[0], self.target[0], module=module)
-
-        self._backward_transformation = TransformationCache.create(
-            backward_class, self.target[0], self.domain[0], module=module)
-
-    def _prep(self, x, spaces, dom):
-        assert issubclass(x.dtype.type,np.floating), \
-            "Argument must be real-valued"
-        spaces = utilities.cast_axis_to_tuple(spaces, len(x.domain))
-        if spaces is None:
-            # this case means that x lives on only one space, which is
-            # identical to the space in the domain of `self`. Otherwise the
-            # input check of LinearOperator would have failed.
-            axes = x.domain_axes[0]
-        else:
-            axes = x.domain_axes[spaces[0]]
-
-        if spaces is None:
-            result_domain = dom
-        else:
-            result_domain = list(x.domain)
-            result_domain[spaces[0]] = dom[0]
-
-        result_field = x.copy_empty(domain=result_domain, dtype=x.dtype)
-        return spaces, axes, result_field
-
-    def _times(self, x, spaces):
-        spaces, axes, result_field = self._prep(x, spaces, self.target)
-
-        if type(self._domain[0]) != RGSpace:
-            new_val = self._forward_transformation.transform(x.val, axes=axes)
-            result_field.set_val(new_val=new_val, copy=True)
-            return result_field
-
-        if self._target[0].harmonic:  # going to harmonic space
-            new_val = self._forward_transformation.transform(x.val, axes=axes)
-            result_field.set_val(new_val=new_val.real+new_val.imag)
-        else:
-            tval = self._domain[0].hermitianize_inverter(x.val, axes)
-            tval = 0.5*((x.val+tval)+1j*(x.val-tval))
-            new_val = self._forward_transformation.transform(tval, axes=axes)
-            result_field.set_val(new_val=new_val.real)
-        return result_field
-
-    def _adjoint_times(self, x, spaces):
-        spaces, axes, result_field = self._prep(x, spaces, self.domain)
-
-        if type(self._domain[0]) != RGSpace:
-            new_val = self._backward_transformation.transform(x.val, axes=axes)
-            result_field.set_val(new_val=new_val, copy=True)
-            return result_field
-
-        if self._domain[0].harmonic:  # going to harmonic space
-            new_val = self._backward_transformation.transform(x.val, axes=axes)
-            result_field.set_val(new_val=new_val.real+new_val.imag)
-        else:
-            tval = self._target[0].hermitianize_inverter(x.val, axes)
-            tval = 0.5*((x.val+tval)+1j*(x.val-tval))
-            new_val = self._backward_transformation.transform(tval, axes=axes)
-            result_field.set_val(new_val=new_val.real)
-        return result_field
-
-    # ---Mandatory properties and methods---
-
-    @property
-    def domain(self):
-        return self._domain
-
-    @property
-    def target(self):
-        return self._target
-
-    @property
-    def unitary(self):
-        return (self._forward_transformation.unitary and
-                self._backward_transformation.unitary)
-
-    # ---Added properties and methods---
-
-    @classmethod
-    def get_default_codomain(cls, domain):
-        """Returns a codomain to the given domain.
-
-        Parameters
-        ----------
-        domain: Space
-            An instance of RGSpace, HPSpace, GLSpace or LMSpace.
-
-        Returns
-        -------
-        target: Space
-            A (more or less perfect) counterpart to "domain" with respect
-            to a FFT operation.
-            Whenever "domain" is an RGSpace, the codomain (and its parameters)
-            are uniquely determined.
-            For GLSpace, HPSpace, and LMSpace, a sensible (but not unique)
-            co-domain is chosen that should work satisfactorily in most
-            situations. For full control however, the user should not rely on
-            this method.
-
-        Raises
-        ------
-        ValueError:
-            if no default codomain is defined for "domain".
-
-        """
-        domain_class = domain.__class__
-        try:
-            codomain_class = cls.default_codomain_dictionary[domain_class]
-        except KeyError:
-            raise ValueError("Unknown domain")
-
-        try:
-            transform_class = cls.transformation_dictionary[(domain_class,
-                                                             codomain_class)]
-        except KeyError:
-            raise ValueError(
-                "No transformation for domain-codomain pair found.")
-
-        return transform_class.get_codomain(domain)

nifty/operators/fft_operator/transformations/rg_transforms.py

@@ -260,7 +260,7 @@ class MPIFFT(Transform):
         p()
 
         if p.has_output:
-            result = p.output_array
+            result = p.output_array.copy()
             if result.shape != val.shape:
                 raise ValueError("Output shape is different than input shape. "
                                  "Maybe fftw tries to optimize the "

nifty/operators/fft_operator/transformations/rgrgtransformation.py

@@ -43,6 +43,8 @@ class RGRGTransformation(Transformation):
         else:
             raise ValueError('Unsupported FFT module:' + module)
 
+        self.harmonic_base = nifty_configuration['harmonic_rg_base']
+
     # ---Mandatory properties and methods---
 
     @property
@@ -144,7 +146,31 @@ class RGRGTransformation(Transformation):
             val = self._transform.domain.weight(val, power=1, axes=axes)
 
         # Perform the transformation
-        Tval = self._transform.transform(val, axes, **kwargs)
+        if self.harmonic_base == 'complex':
+            Tval = self._transform.transform(val, axes, **kwargs)
+        else:
+            if issubclass(val.dtype.type, np.complexfloating):
+                Tval_real = self._transform.transform(val.real, axes,
+                                                      **kwargs)
+                Tval_imag = self._transform.transform(val.imag, axes,
+                                                      **kwargs)
+                if self.codomain.harmonic:
+                    Tval_real.data.real += Tval_real.data.imag
+                    Tval_real.data.imag = \
+                        Tval_imag.data.real + Tval_imag.data.imag
+                else:
+                    Tval_real.data.real -= Tval_real.data.imag
+                    Tval_real.data.imag = \
+                        Tval_imag.data.real - Tval_imag.data.imag
+
+                Tval = Tval_real
+            else:
+                Tval = self._transform.transform(val, axes, **kwargs)
+                if self.codomain.harmonic:
+                    Tval.data.real += Tval.data.imag
+                else:
+                    Tval.data.real -= Tval.data.imag
+                Tval = Tval.real
 
         if not self._transform.codomain.harmonic:
             # correct for inverse fft.

nifty/spaces/rg_space/rg_space.py

@@ -36,7 +36,7 @@ from d2o import distributed_data_object,\
                 STRATEGIES as DISTRIBUTION_STRATEGIES
 
 from nifty.spaces.space import Space
-
+from nifty.config import nifty_configuration
 
 class RGSpace(Space):
     """
@@ -122,33 +122,36 @@ class RGSpace(Space):
 #        return fixed_points
 
     def hermitianize_inverter(self, x, axes):
-        # calculate the number of dimensions the input array has
-        dimensions = len(x.shape)
-        # prepare the slicing object which will be used for mirroring
+        if nifty_configuration['harmonic_rg_base'] == 'real':
+            return x
+        else: