1 files changed, 32 insertions, 5 deletions
diff --git a/Wrappers/Python/ccpi/optimisation/ops.py b/Wrappers/Python/ccpi/optimisation/ops.py
index 450b084..3845621 100755
--- a/Wrappers/Python/ccpi/optimisation/ops.py
+++ b/Wrappers/Python/ccpi/optimisation/ops.py
@@ -24,26 +24,49 @@ from ccpi.framework import AcquisitionData
 from ccpi.framework import ImageData
 from ccpi.framework import ImageGeometry
 from ccpi.framework import AcquisitionGeometry
-
+from numbers import Number
 # Maybe operators need to know what types they take as inputs/outputs
 # to not just use generic DataContainer
 
 
 class Operator(object):
+    '''Operator that maps from a space X -> Y'''
+    def __init__(self, **kwargs):
+        self.scalar = 1
+    def is_linear(self):
+        '''Returns if the operator is linear'''
+        return False
     def direct(self,x, out=None):
-        return x
-    def adjoint(self,x, out=None):
-        return x
+        raise NotImplementedError
     def size(self):
         # To be defined for specific class
         raise NotImplementedError
-    def get_max_sing_val(self):
+    def norm(self):
         raise NotImplementedError
     def allocate_direct(self):
+        '''Allocates memory on the Y space'''
         raise NotImplementedError
     def allocate_adjoint(self):
+        '''Allocates memory on the X space'''
+        raise NotImplementedError
+    def range_dim(self):
         raise NotImplementedError
+    def domain_dim(self):
+        raise NotImplementedError
+    def __rmul__(self, other):
+        '''reverse multiplication of Operator with number sets the variable scalar in the Operator'''
+        assert isinstance(other, Number)
+        self.scalar = other
+        return self
 
+class LinearOperator(Operator):
+    '''Operator that maps from a space X -> Y'''
+    def is_linear(self):
+        '''Returns if the operator is linear'''
+        return True
+    def adjoint(self,x, out=None):
+        raise NotImplementedError
+        
 class Identity(Operator):
     def __init__(self):
         self.s1 = 1.0
@@ -75,12 +98,16 @@ class TomoIdentity(Operator):
         super(TomoIdentity, self).__init__()
         
     def direct(self,x,out=None):
+        if self.scalar != 1:
+            x *= self.scalar
         if out is None:
             return x.copy()
         else:
             out.fill(x)
     
     def adjoint(self,x, out=None):
+        if self.scalar != 1:
+            x *= self.scalar
         if out is None:
             return x.copy()
         else: