Add FaustLazyLinearOp.imag and its unit test.

wrapper/python/pyfaust/lazylinop.py

@@ -445,6 +445,18 @@ class LazyLinearOp:
                                 root_obj=self._root_obj)
         return new_op
 
+    @property
+    def imag(self):
+        """
+        Returns the LazyLinearOp for imag.
+        """
+        self._checkattr('imag')
+        new_op = self.__class__(init_lambda=lambda:
+                                (self._lambda_stack()).imag,
+                                shape=self.shape,
+                                root_obj=self._root_obj)
+        return new_op
+
 
     @staticmethod
     def isLazyLinearOp(obj):

wrapper/python/pyfaust/tests/TestLazyLinearOp.py

@@ -179,5 +179,11 @@ class TestLazyLinearOpFaust(unittest.TestCase):
         lcF = lcF.real
         self.assertAlmostEqual(LA.norm(lcF.toarray()-cF.real.toarray()), 0)
 
+    def test_imag(self):
+        cF = pf.rand(10, 15, field='complex')
+        lcF = LazyLinearOp.create(cF)
+        lcF = lcF.imag
+        self.assertAlmostEqual(LA.norm(lcF.toarray()-cF.imag.toarray()), 0)
+
 if '__main__' == __name__:
     unittest.main()