Index: DataLoader/test/utest_manipulations.py
===================================================================
--- DataLoader/test/utest_manipulations.py	(revision 9198b8310ebd4e2c3eabca485fa5c08200add7cf)
+++ DataLoader/test/utest_manipulations.py	(revision 442f42fc528a8171701cedfb4110b6e4fabe9210)
@@ -2,9 +2,10 @@
     Unit tests for data manipulations
 """
+#TODO: what happens if you add a Data1D to a Data2D?
 
 import unittest
 import numpy, math
 from DataLoader.loader import  Loader
-from DataLoader.data_info import Data1D
+from DataLoader.data_info import Data1D, Data2D
  
 import os.path
@@ -128,4 +129,113 @@
             self.assertEqual(result.dy[i], 6.0*0.5/4.0)
             
+class manip_2D(unittest.TestCase):
+    
+    def setUp(self):
+        # Create two data sets to play with
+        x_0 = 2.0*numpy.ones([5,4])
+        dx_0 = 0.5*numpy.ones([5,4])
+        self.data = Data2D(x_0, dx_0)
+        
+        y = numpy.ones([5,4])
+        dy = numpy.ones([5,4])
+        self.data2 = Data2D(y, dy)
+        
+        
+    def test_load(self):
+        """
+            Test whether the test file was loaded properly
+        """
+        # There should be 5 entries in the file
+        self.assertEqual(numpy.size(self.data.data, 0), 5)
+        self.assertEqual(numpy.size(self.data.data, 1), 4)
+        
+        for i in range(5):
+            for j in range(4):
+                # All y-error values should be 0.5
+                self.assertEqual(self.data.err_data[i][j], 0.5)    
+                
+                # All y values should be 2.0
+                self.assertEqual(self.data.data[i][j], 2.0)    
+        
+    def test_add(self):
+        result = self.data2+self.data
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], 3.0)
+                self.assertEqual(result.err_data[i][j], math.sqrt(0.5**2+1.0))
+        
+    def test_sub(self):
+        result = self.data2-self.data
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], -1.0)
+                self.assertEqual(result.err_data[i][j], math.sqrt(0.5**2+1.0))
+        
+    def test_mul(self):
+        result = self.data2*self.data
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], 2.0)
+                self.assertEqual(result.err_data[i][j], math.sqrt((0.5*1.0)**2+(1.0*2.0)**2))
+        
+    def test_div(self):
+        result = self.data2/self.data
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], 0.5)
+                self.assertEqual(result.err_data[i][j], math.sqrt((1.0/2.0)**2+(0.5*1.0/4.0)**2))
+        
+    def test_radd(self):
+        result = self.data+3.0
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], 5.0)
+                self.assertEqual(result.err_data[i][j], 0.5)
+            
+        result = 3.0+self.data
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], 5.0)
+                self.assertEqual(result.err_data[i][j], 0.5)
+            
+    def test_rsub(self):
+        result = self.data-3.0
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], -1.0)
+                self.assertEqual(result.err_data[i][j], 0.5)
+            
+        result = 3.0-self.data
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], 1.0)
+                self.assertEqual(result.err_data[i][j], 0.5)
+            
+    def test_rmul(self):
+        result = self.data*3.0
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], 6.0)
+                self.assertEqual(result.err_data[i][j], 1.5)
+            
+        result = 3.0*self.data
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], 6.0)
+                self.assertEqual(result.err_data[i][j], 1.5)
+            
+    def test_rdiv(self):
+        result = self.data/4.0
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], 0.5)
+                self.assertEqual(result.err_data[i][j], 0.125)
+            
+        result = 6.0/self.data
+        for i in range(5):
+            for j in range(4):
+                self.assertEqual(result.data[i][j], 3.0)
+                self.assertEqual(result.err_data[i][j], 6.0*0.5/4.0)
+            
 
 if __name__ == '__main__':
