symmetric sparsity constraint implemented

proxtoolbox/Problems/OrbitalTomog/phase.py

@@ -66,6 +66,12 @@ class Phase(Problem):
             used_proxoperators[0] = 'P_Sparsity_real'
         elif self.config['constraint'] == 'sparse complex':
             used_proxoperators[0] = 'P_Sparsity'
+        elif self.config['constraint'] in ['symmetric sparse real', 'sparse symmetric real']:
+            used_proxoperators[0] = 'P_Sparsity_Symmetric_real'
+        elif self.config['constraint'] in ['symmetric sparse complex', 'symmetric sparse complex']:
+            used_proxoperators[0] = 'P_Sparsity_Symmetric'
+        else:
+            raise ValueError('Constraint not recognized')
 
         # Projector 2 (k / Fourier space)
 #         used_proxoperators[1] = 'P_M'  # 'Approx_P_FreFra_Poisson'

proxtoolbox/ProxOperators/P_Sparsity.py

@@ -74,3 +74,28 @@ class P_Sparsity_real(P_Sparsity):
 
     def work(self, u):
         return super(P_Sparsity_real, self).work(u.real)
+
+
+class P_Sparsity_Symmetric(P_Sparsity):
+    def __init__(self, config):
+        super(P_Sparsity_Symmetric, self).__init__(config=config)
+        self.symmetry = config['symmetry type'] # antisymmetric = -1, symmetric = 1
+        self.symmetry_axis = config['symmetry axis']  # -1 for last, 0 for first, 'both', 'all' or None for full flip
+
+    def work(self, u):
+        if self.symmetry_axis in ['both', 'all']:
+            mirror = np.flip(u, axis=None)
+        else:
+            mirror = np.flip(u, axis=self.symmetry_axis)
+        inp = (u + self.symmetry * mirror) / 2
+        out = super(P_Sparsity_Symmetric, self).work(inp)
+        return out
+
+
+class P_Sparsity_Symmetric_real(P_Sparsity_Symmetric):
+    def __init__(self, config):
+        super(P_Sparsity_Symmetric_real, self).__init__(config=config)
+
+    def work(self, u):
+        out = super(P_Sparsity_Symmetric_real, self).work(u.real)
+        return out
\ No newline at end of file

proxtoolbox/ProxOperators/P_binary.py

 import numpy as np
 from numpy import shape, real, zeros
-from proxoperators import ProxOperator
+from .proxoperators import ProxOperator
 #original matlab comment
 #             written on May 23, 2002 by 
 #                   Russell Luke