add projectors, propagators, and initializers

tests/tools/test_initializers.py

@@ -0,0 +1,24 @@
+from __future__ import division, print_function, absolute_import
+
+from CDTools.tools import initializers
+import numpy as np
+import torch as t
+
+
+
+def test_gaussian():
+    # Generate gaussian as a numpy array (square array)
+    shape = [10, 10]
+    sigma = [2.5, 2.5]
+    center = ((shape[0]-1)/2, (shape[1]-1)/2)
+    y, x = np.mgrid[:shape[0], :shape[1]]
+    np_result = 10*np.exp(-((x-center[1])/sigma[1])**2-((y-center[0])/sigma[0])**2)
+    assert(np.allclose(initializers.gaussian([10, 10], 10, [2.5, 2.5]), np_result))
+
+    # Generate gaussian as a numpy array (rectangular array)
+    shape = [10, 5]
+    sigma = [2.5, 2.5]
+    center = ((shape[0]-1)/2, (shape[1]-1)/2)
+    y, x = np.mgrid[:shape[0], :shape[1]]
+    np_result = 10*np.exp(-((x-center[1])/sigma[1])**2-((y-center[0])/sigma[0])**2)
+    assert(np.allclose(initializers.gaussian([10, 5], 10, [2.5, 2.5]), np_result))