updating DIRECTORY.md

DIRECTORY.md

@@ -1076,7 +1076,6 @@
   * [Non Preemptive Shortest Job First](scheduling/non_preemptive_shortest_job_first.py)
   * [Round Robin](scheduling/round_robin.py)
   * [Shortest Job First](scheduling/shortest_job_first.py)
-  * [Split Workload](scheduling/split_workload.py)
 
 ## Searches
   * [Binary Search](searches/binary_search.py)
@@ -1140,6 +1139,7 @@
   * [Shell Sort](sorts/shell_sort.py)
   * [Shrink Shell Sort](sorts/shrink_shell_sort.py)
   * [Slowsort](sorts/slowsort.py)
+  * [Split Workload](sorts/split_workload.py)
   * [Stooge Sort](sorts/stooge_sort.py)
   * [Strand Sort](sorts/strand_sort.py)
   * [Tim Sort](sorts/tim_sort.py)

scheduling/split_workload.py

@@ -1,78 +0,0 @@
-from math import fabs
-
-
-def split_list(timings: list) -> tuple:
-    """
-
-    this is a case of the partition problem.
-    it accepts a multiset ( list ) of positive integers,
-    distributes them, and returns a tuple, containing two lists,
-    with minimal difference between their sums
-
-    >>> split_list([27, 21, 92, 87, 1, 32])
-    ([27, 21, 87], [92, 1, 32], 10)
-    >>> split_list([52, 385, 9956, 25, 2367, 1111, 17, 925])
-    ([9956], [52, 385, 25, 2367, 1111, 17, 925], 5074)
-    >>> split_list([12, 10, 11, 9])
-    ([10, 11], [12, 9], 0)
-    >>> split_list([-1551, 2712, 2325, 2623])
-    ([1551, 2712], [2325, 2623], 685)
-    >>> split_list(["12.5", "10", "11", "9"])
-    ([10, 11], [12.5, 9], 0.5)
-    >>> split_list(["twelve", "ten", "eleven", "nine"])
-    ([0], [0, 0, 0], 0)
-
-    """
-
-    result = None
-
-    def split_workload(arr: list) -> tuple:
-        if len(arr) == 0:
-            return ([], [], 0)
-        if len(arr) == 1:
-            return ([arr[0]], [], 1)
-        else:
-            n = len(arr)
-            smallest_diff = float("inf")
-            if any(c < 0 for c in arr):
-                raise ValueError("Numbers can only be non-negative")
-            for i in range(1, 2**n - 1):
-                indices = [j for j in range(n) if (i & (1 << j)) != 0]
-                distributed_timings_1 = [arr[j] for j in indices]
-                distributed_timings_2 = [arr[j] for j in range(n) if j not in indices]
-                diff = abs(sum(distributed_timings_1) - sum(distributed_timings_2))
-                smallest_diff = min(smallest_diff, diff)
-                result = (
-                    distributed_timings_1,
-                    distributed_timings_2,
-                    smallest_diff,
-                )
-            return result
-
-    try:
-        result = split_workload(timings)
-    except TypeError:
-        for val in range(0, len(timings)):
-            current_element = timings[val]
-            if (
-                isinstance(current_element, str)
-                and current_element.replace(".", "", 1).isdigit()
-            ):
-                is_current_elem_int = float(current_element).is_integer()
-                if not is_current_elem_int:
-                    timings[val] = fabs(float(current_element))
-                else:
-                    timings[val] = abs(int(float(current_element)))
-            else:
-                timings[val] = 0
-        result = split_workload(timings)
-
-    except ValueError:
-        timings = [c * -1 if c < 0 else c for c in timings]
-        result = split_workload(timings)
-
-    return result
-
-
-if __name__ == "__main__":
-    __import__("doctest").testmod()

sorts/split_workload.py

@@ -0,0 +1,72 @@
+from typing import List, Tuple, Union
+
+
+def split_list(timings: List[Union[int, float, str]]) -> Tuple[List[Union[int, float]]]:
+    """
+
+    This algorithm is a brute-force search over (nearly) all 2^n
+    possible partitions and was created for educational purposes.
+    the asymptotic runtime of this code is: O(n * 2^n)
+
+    this is a case of the partition problem.
+    it accepts a multiset ( list ) of positive integers,
+    distributes them, and returns a tuple, containing two lists,
+    with minimal difference between their sums
+
+    >>> split_list([27, 21, 92, 87, 1, 32])
+    ([27, 21, 87], [92, 1, 32], 10)
+    >>> split_list([52, 385, 9956, 25, 2367, 1111, 17, 925])
+    ([9956], [52, 385, 25, 2367, 1111, 17, 925], 5074)
+    >>> split_list([12, 10, 11, 9])
+    ([10, 11], [12, 9], 0)
+    >>> split_list([-1551, 2712, 2325, 2623])
+    ([1551, 2712], [2325, 2623], 685)
+    >>> split_list(["12.5", "10", "11", "9"])
+    ([10, 11], [12.5, 9], 0.5)
+    >>> split_list(["twelve", "ten", "eleven", "nine"])
+    Traceback (most recent call last):
+    ValueError: only numbers please
+
+    """
+
+    for i, current_element in enumerate(timings):
+        if (
+            isinstance(current_element, str)
+            and current_element.replace(".", "", 1).isdigit()
+        ):
+            is_current_elem_int = float(current_element).is_integer()
+            if not is_current_elem_int:
+                timings[i] = abs(float(current_element))
+            else:
+                timings[i] = abs(int(float(current_element)))
+        elif isinstance(current_element, (int, float)):
+            timings[i] = abs(current_element)
+        else:
+            raise ValueError("only numbers please")
+
+    if len(timings) == 0:
+        return ([], [], 0)
+    elif len(timings) == 1:
+        return ([timings[0]], [], 1)
+    else:
+        result = None
+        n = len(timings)
+        smallest_diff = float("inf")
+        all_nums_positive = [c >= 0 for c in timings]
+        for i in range(1, 2**n - 1):
+            indices = [j for j in range(n) if (i & (1 << j)) != 0]
+            distributed_timings_1 = [timings[j] for j in indices]
+            distributed_timings_2 = [timings[j] for j in range(n) if j not in indices]
+            diff = abs(sum(distributed_timings_1) - sum(distributed_timings_2))
+            if diff < smallest_diff:
+                smallest_diff = diff
+                result = (
+                    distributed_timings_1,
+                    distributed_timings_2,
+                    smallest_diff,
+                )
+        return result
+
+
+if __name__ == "__main__":
+    __import__("doctest").testmod()