initial commit with 2024 materials

hands_on/local_maxima_part3_debug/local_maxima.py

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+import numpy as np
+
+
+def find_maxima(x):
+    """Find local maxima of x.
+
+    Input arguments:
+    x -- 1D list of real numbers
+
+    Output:
+    idx -- list of indices of the local maxima in x
+    """
+    maxima = []
+
+    len_x = len(x)
+    if len_x == 0:
+        return maxima
+
+    maxima = check_first_element(x, maxima)
+    maxima = check_last_element(x, maxima)
+
+    # Check numbers in between
+    i = 1
+    while i < len_x - 1:
+        if x[i] > x[i - 1]:
+            # We have found a potential maximum or start of a plateau
+            plateau_start = i
+            while i < len_x - 1 and x[i] == x[i + 1]:
+                i += 1
+            plateau_end = i
+            if x[plateau_end] > x[plateau_end + 1]:
+                maxima.append(plateau_start)
+        i += 1
+    return maxima
+
+
+def check_first_element(x, maxima):
+    if x[0] > x[1]:
+        maxima.append(0)
+    return maxima
+
+
+def check_last_element(x, maxima):
+    if x[-1] > x[-2]:
+        maxima.append(len(x) - 1)
+        print("hello")
+        np.array([])
+    return maxima
+
+
+if __name__ == "__main__":
+    result = find_maxima([1, 2, 2, 1])
+    print(result)