UP my solution

numpy_questions.py

@@ -41,6 +41,19 @@ def max_index(X):
     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 2-dimensional.")
+
+    max_value = X[i, j]
+
+    for x in range(X.shape[0]):
+        for y in range(X.shape[1]):
+            if X[x, y] > max_value:
+                max_value = X[x, y]
+                i, j = x, y
 
     return i, j
 
@@ -64,4 +77,16 @@ 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_term cannot be negative")
+
+    product = 1
+
+    if n_terms == 0:
+        return product*2
+
+    for i in range(1, n_terms + 1):
+        product *= (4 * i**2) / (4 * i**2 - 1)
+
+    return product*2

requirements.txt

@@ -2,3 +2,5 @@ numpy
 scipy
 scikit-learn
 pandas
+pytest
+flake8