add find_maxima and testing for find_maxima

hands_on/local_maxima/local_maxima.py

@@ -7,4 +7,17 @@ def find_maxima(x):
     Output:
     idx -- list of indices of the local maxima in x
     """
-    return []
+    maxima= []
+    for i, val in enumerate(x):
+        if i == 0 and val > x[i+1]:
+            maxima.append(i)
+        elif i == len(x) -1 and val > x[len(x) -2]:
+            maxima.append(i)
+        else:
+            if val > x[i-1] and val > x[i+1]:
+                maxima.append(i)
+    return maxima
+
+if __name__ == "__main__":
+    idx = find_maxima([1,3,-2,0,2,1])
+    print(idx)

hands_on/local_maxima/test_local_maxima.py

@@ -0,0 +1,41 @@
+from local_maxima import find_maxima
+
+def test_local_maxima_first():
+    values = [1,3, -2, 0,2,1]
+    expected = [1, 4]
+
+    result = find_maxima(values)
+
+    assert result == expected
+
+def test_local_maxima_second():
+    values = [4, 2, 1, 3, 1, 5]
+    expected = [0,3,5]
+
+    result = find_maxima(values)
+
+    assert result == expected
+
+def test_local_maxima_third():
+    values = []
+    expected = []
+
+    result = find_maxima(values)
+
+    assert result == expected
+
+def test_local_maxima_fourth():
+    values = [1,2,2,1]
+    expected = []
+
+    result = find_maxima(values)
+
+    assert result == expected
+
+def test_local_maxima_fifth():
+    values = [1,2,2,3,1]
+    expected = [3]
+
+    result = find_maxima(values)
+
+    assert result == expected