more convenient handling of 'unitary' property

nifty/library/log_normal_wiener_filter_curvature.py

@@ -38,10 +38,6 @@ class LogNormalWienerFilterCurvature(InversionEnabler, EndomorphicOperator):
     def self_adjoint(self):
         return True
 
-    @property
-    def unitary(self):
-        return False
-
     def _times(self, x):
         part1 = self.S.inverse_times(x)
         part3 = self._fft.adjoint_times(self._expp_sspace * self._fft(x))

nifty/library/nonlinear_power_curvature.py

@@ -25,10 +25,6 @@ class NonlinearPowerCurvature(InversionEnabler, EndomorphicOperator):
     def self_adjoint(self):
         return True
 
-    @property
-    def unitary(self):
-        return False
-
     def _times(self, x):
         result = None
         for sample in self.sample_list:

nifty/library/response_operators.py

@@ -31,10 +31,6 @@ class LinearizedSignalResponse(LinearOperator):
     def target(self):
         return self.Instrument.target
 
-    @property
-    def unitary(self):
-        return False
-
 
 class LinearizedPowerResponse(LinearOperator):
     def __init__(self, Instrument, nonlinearity, FFT, Projection, t, m):
@@ -74,7 +70,3 @@ class LinearizedPowerResponse(LinearOperator):
     @property
     def target(self):
         return self.Instrument.target
-
-    @property
-    def unitary(self):
-        return False

nifty/library/wiener_filter_curvature.py

@@ -36,10 +36,6 @@ class WienerFilterCurvature(InversionEnabler, EndomorphicOperator):
     def self_adjoint(self):
         return True
 
-    @property
-    def unitary(self):
-        return False
-
     def _times(self, x):
         res = self.R.adjoint_times(self.N.inverse_times(self.R(x)))
         res += self.S.inverse_times(x)

nifty/operators/composed_operator.py

@@ -37,8 +37,6 @@ class ComposedOperator(LinearOperator):
         The NIFTy.space in which the operator is defined.
     target : DomainTuple
         The NIFTy.space in which the outcome of the operator lives
-    unitary : boolean
-        Indicates whether the Operator is unitary or not.
     """
 
     def __init__(self, operators):
@@ -63,10 +61,6 @@ class ComposedOperator(LinearOperator):
     def target(self):
         return self._operator_store[-1].target
 
-    @property
-    def unitary(self):
-        return False
-
     def _times(self, x):
         return self._times_helper(x, func='times')
 

nifty/operators/direct_smoothing_operator.py

@@ -42,10 +42,6 @@ class DirectSmoothingOperator(EndomorphicOperator):
     def self_adjoint(self):
         return True
 
-    @property
-    def unitary(self):
-        return False
-
     def _precompute(self, x):
         """ Does precomputations for Gaussian smoothing on a 1D irregular grid.
 

nifty/operators/dof_projection_operator.py

@@ -95,7 +95,3 @@ class DOFProjectionOperator(LinearOperator):
     @property
     def target(self):
         return self._target
-
-    @property
-    def unitary(self):
-        return False

nifty/operators/endomorphic_operator.py

@@ -34,8 +34,6 @@ class EndomorphicOperator(LinearOperator):
     target : DomainTuple
         The domain in which the outcome of the operator lives. As the Operator
         is endomorphic this is the same as its domain.
-    unitary : boolean
-        Indicates whether the Operator is unitary or not.
     self_adjoint : boolean
         Indicates whether the operator is self_adjoint or not.
     """

nifty/operators/fft_smoothing_operator.py

@@ -35,7 +35,3 @@ class FFTSmoothingOperator(EndomorphicOperator):
     @property
     def self_adjoint(self):
         return True
-
-    @property
-    def unitary(self):
-        return False

nifty/operators/laplace_operator.py

@@ -70,10 +70,6 @@ class LaplaceOperator(EndomorphicOperator):
     def domain(self):
         return self._domain
 
-    @property
-    def unitary(self):
-        return False
-
     @property
     def self_adjoint(self):
         return False

nifty/operators/linear_operator.py

@@ -64,15 +64,15 @@ class LinearOperator(with_metaclass(
         """
         raise NotImplementedError
 
-    @abc.abstractproperty
+    @property
     def unitary(self):
         """
         unitary : boolean
             States whether the Operator is unitary or not.
-            Every Operator which inherits from the abstract LinearOperator
-            base class must have this attribute.
+            Since the majority of operators will not be unitary, this property
+            returns False, unless it is overridden in a subclass.
         """
-        raise NotImplementedError
+        return False
 
     def __call__(self, x):
         return self.times(x)

nifty/operators/response_operator.py

@@ -33,8 +33,6 @@ class ResponseOperator(LinearOperator):
         The domain on which the Operator's input Field lives.
     target : DomainTuple
         The domain in which the outcome of the operator lives.
-    unitary : boolean
-        Indicates whether the Operator is unitary or not.
 
     Raises
     ------
@@ -78,10 +76,6 @@ class ResponseOperator(LinearOperator):
     def target(self):
         return self._target
 
-    @property
-    def unitary(self):
-        return False
-
     def _times(self, x):
         res = self._composed_kernel.times(x)
         res = self._composed_exposure.times(res)

nifty/operators/smoothness_operator.py

@@ -38,10 +38,6 @@ class SmoothnessOperator(EndomorphicOperator):
     def domain(self):
         return self._laplace._domain
 
-    @property
-    def unitary(self):
-        return False
-
     @property
     def self_adjoint(self):
         return False