UP my solution

numpy_questions.py

@@ -1,7 +1,6 @@
 """Assignment - using numpy and making a PR.
 
 The goals of this assignment are:
-    * Use numpy in practice with two easy exercises.
     * Use automated tools to validate the code (`pytest` and `flake8`)
     * Submit a Pull-Request on github to practice `git`.
 
@@ -40,7 +39,15 @@ def max_index(X):
     i = 0
     j = 0
 
-    # TODO
+    if not isinstance(X, np.ndarray):
+        raise ValueError("Input must be a numpy array.")
+    if X.ndim != 2:
+        raise ValueError("Input array must be 2D.")
+
+    # Find the flattened index of the maximum
+    idx_flat = np.argmax(X)
+    # Update i and j using the flattened index and array shape
+    i, j = np.unravel_index(idx_flat, X.shape)
 
     return i, j
 
@@ -64,4 +71,12 @@ 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:
+        return 2.0
+
+    # Calculate the product terms using the formula for pi/2
+    k = np.arange(1, n_terms + 1)
+    half_pi = np.prod(4.0 * k**2 / (4.0 * k**2 - 1.0))
+
+    return 2.0 * half_pi