Ahmed semah

numpy_questions.py

@@ -41,7 +41,11 @@ def max_index(X):
     j = 0
 
     # TODO
-
+    if not isinstance(X, np.ndarray):
+        raise ValueError("Input is not a numpy array")
+    if X.ndim != 2:
+        raise ValueError("Input is not a 2D array")
+    i, j = np.unravel_index(np.argmax(X), X.shape)
     return i, j
 
 
@@ -64,4 +68,13 @@ def wallis_product(n_terms):
     """
     # XXX : The n_terms is an int that corresponds to the number of
     # terms in the product. For example 10000.
-    return 0.
+
+    if n_terms < 0:
+        raise ValueError("n_terms should be a positive integer")
+    if n_terms == 0:
+        return 2.
+
+    pi = 1.
+    for i in range(1, n_terms+1):
+        pi *= 4*i**2/(4*i**2-1)
+    return 2*pi