Better plots

test.py

@@ -329,7 +329,7 @@ def test_against_wdft(nxdirty, nydirty, epsilon, nchan, nrow):
 
     ax = fig.add_subplot(2, 2, 3)
     ax.set_title('relative error')
-    im = ax.imshow(np.abs(res1-res0)/res1)
+    im = ax.imshow(np.abs(res1-res0)/np.max([ np.abs(res0), np.abs(res1) ]))
     fig.colorbar(im, ax=ax)
 
     ax = fig.add_subplot(2, 2, 4)