UP my solution

numpy_questions.py

@@ -16,6 +16,7 @@
 errors by calling `flake8` at the root of the repo.
 """
 import numpy as np
+import math
 
 
 def max_index(X):
@@ -37,10 +38,21 @@ def max_index(X):
         If the input is not a numpy array or
         if the shape is not 2D.
     """
+    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.")
+
     i = 0
     j = 0
+    max = -math.inf
 
-    # TODO
+    for row in range(X.shape[0]):
+        for column in range(X.shape[1]):
+            if X[row][column] > max:
+                i = row
+                j = column
+                max = X[row][column]
 
     return i, j
 
@@ -62,6 +74,12 @@ def wallis_product(n_terms):
     pi : float
         The approximation of order `n_terms` of pi using the Wallis product.
     """
-    # 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  # Base case: Approximation of pi with no terms
+
+    product = 1.0
+    for n in range(1, n_terms + 1):
+        term = (4 * n ** 2) / ((4 * n ** 2) - 1)
+        product *= term
+
+    return 2 * product