code: Add laplace noise

code/lib/lmdk_lib.py

@@ -68,6 +68,21 @@ def randomized_response(r, epsilon):
     return not r
 
 
+
+def add_laplace_noise(value, sens, epsilon):
+  '''
+    Add random noise to a data value.
+
+    Parameteres:
+      value   - The value to add noise to.
+      sens    - The query function sensitivity.
+      epsilon - The privacy budget. 
+    Returns:
+      The value with the noise.
+  '''
+  return np.random.laplace(value, sens/epsilon)
+
+
 def draw_line(line, x, label, marker):
   axis_x = list(range(len(x)))
   # plt.xticks(axis_x, x)