style: preserve upstream LF line endings

Author: mohammmad357

sorts/odd_even_transposition_parallel.py

@@ -1,196 +1,196 @@
-"""
-This is an implementation of odd-even transposition sort.
-
-It works by performing a series of parallel swaps between odd and even pairs of
-variables in the list.
-
-This implementation represents each variable in the list with a process and
-each process communicates with its neighboring processes in the list to perform
-comparisons.
-They are synchronized with locks and message passing but other forms of
-synchronization could be used.
-"""
-
-import multiprocessing as mp
-
-# lock used to ensure that two processes do not access a pipe at the same time
-# NOTE This breaks testing on build runner. May work better locally
-# process_lock = mp.Lock()
-
-"""
-The function run by the processes that sorts the list
-
-position = the position in the list the process represents, used to know which
-            neighbor we pass our value to
-value = the initial value at list[position]
-LSend, RSend = the pipes we use to send to our left and right neighbors
-LRcv, RRcv = the pipes we use to receive from our left and right neighbors
-resultPipe = the pipe used to send results back to main
-"""
-
-
-def oe_process(
-    position,
-    value,
-    l_send,
-    r_send,
-    lr_cv,
-    rr_cv,
-    result_pipe,
-    multiprocessing_context,
-    phases: int,
-) -> None:
-    process_lock = multiprocessing_context.Lock()
-
-    # we perform n swaps since after n swaps we know we are sorted
-    # we *could* stop early if we are sorted already, but it takes as long to
-    # find out we are sorted as it does to sort the list with this algorithm
-    for i in range(phases):
-        if (i + position) % 2 == 0 and r_send is not None:
-            # send your value to your right neighbor
-            with process_lock:
-                r_send[1].send(value)
-
-            # receive your right neighbor's value
-            with process_lock:
-                temp = rr_cv[0].recv()
-
-            # take the lower value since you are on the left
-            value = min(value, temp)
-        elif (i + position) % 2 != 0 and l_send is not None:
-            # send your value to your left neighbor
-            with process_lock:
-                l_send[1].send(value)
-
-            # receive your left neighbor's value
-            with process_lock:
-                temp = lr_cv[0].recv()
-
-            # take the higher value since you are on the right
-            value = max(value, temp)
-    # after all swaps are performed, send the values back to main
-    result_pipe[1].send(value)
-
-
-"""
-the function which creates the processes that perform the parallel swaps
-
-arr = the list to be sorted
-"""
-
-
-def odd_even_transposition(arr):
-    """
-    >>> odd_even_transposition(list(range(10)[::-1])) == sorted(list(range(10)[::-1]))
-    True
-    >>> odd_even_transposition(["a", "x", "c"]) == sorted(["x", "a", "c"])
-    True
-    >>> odd_even_transposition([1.9, 42.0, 2.8]) == sorted([1.9, 42.0, 2.8])
-    True
-    >>> odd_even_transposition([False, True, False]) == sorted([False, False, True])
-    True
-    >>> odd_even_transposition([1, 32.0, 9]) == sorted([False, False, True])
-    False
-    >>> odd_even_transposition([1, 32.0, 9]) == sorted([1.0, 32, 9.0])
-    True
-    >>> unsorted_list = [-442, -98, -554, 266, -491, 985, -53, -529, 82, -429]
-    >>> odd_even_transposition(unsorted_list) == sorted(unsorted_list)
-    True
-    >>> unsorted_list = [-442, -98, -554, 266, -491, 985, -53, -529, 82, -429]
-    >>> odd_even_transposition(unsorted_list) == sorted(unsorted_list + [1])
-    False
-    """
-    # spawn method is considered safer than fork
-    multiprocessing_context = mp.get_context("spawn")
-
-    process_array_ = []
-    result_pipe = []
-    # initialize the list of pipes where the values will be retrieved
-    for _ in arr:
-        result_pipe.append(multiprocessing_context.Pipe())
-    # creates the processes
-    # the first and last process only have one neighbor so they are made outside
-    # of the loop
-    temp_rs = multiprocessing_context.Pipe()
-    temp_rr = multiprocessing_context.Pipe()
-    process_array_.append(
-        multiprocessing_context.Process(
-            target=oe_process,
-            args=(
-                0,
-                arr[0],
-                None,
-                temp_rs,
-                None,
-                temp_rr,
-                result_pipe[0],
-                multiprocessing_context,
-                len(arr),
-            ),
-        )
-    )
-    temp_lr = temp_rs
-    temp_ls = temp_rr
-
-    for i in range(1, len(arr) - 1):
-        temp_rs = multiprocessing_context.Pipe()
-        temp_rr = multiprocessing_context.Pipe()
-        process_array_.append(
-            multiprocessing_context.Process(
-                target=oe_process,
-                args=(
-                    i,
-                    arr[i],
-                    temp_ls,
-                    temp_rs,
-                    temp_lr,
-                    temp_rr,
-                    result_pipe[i],
-                    multiprocessing_context,
-                    len(arr),
-                ),
-            )
-        )
-        temp_lr = temp_rs
-        temp_ls = temp_rr
-
-    process_array_.append(
-        multiprocessing_context.Process(
-            target=oe_process,
-            args=(
-                len(arr) - 1,
-                arr[len(arr) - 1],
-                temp_ls,
-                None,
-                temp_lr,
-                None,
-                result_pipe[len(arr) - 1],
-                multiprocessing_context,
-                len(arr),
-            ),
-        )
-    )
-
-    # start the processes
-    for p in process_array_:
-        p.start()
-
-    # wait for the processes to end and write their values to the list
-    for p in range(len(result_pipe)):
-        arr[p] = result_pipe[p][0].recv()
-        process_array_[p].join()
-    return arr
-
-
-# creates a reverse sorted list and sorts it
-def main() -> None:
-    arr = list(range(10, 0, -1))
-    print("Initial List")
-    print(*arr)
-    arr = odd_even_transposition(arr)
-    print("Sorted List\n")
-    print(*arr)
-
-
-if __name__ == "__main__":
-    main()
+"""
+This is an implementation of odd-even transposition sort.
+
+It works by performing a series of parallel swaps between odd and even pairs of
+variables in the list.
+
+This implementation represents each variable in the list with a process and
+each process communicates with its neighboring processes in the list to perform
+comparisons.
+They are synchronized with locks and message passing but other forms of
+synchronization could be used.
+"""
+
+import multiprocessing as mp
+
+# lock used to ensure that two processes do not access a pipe at the same time
+# NOTE This breaks testing on build runner. May work better locally
+# process_lock = mp.Lock()
+
+"""
+The function run by the processes that sorts the list
+
+position = the position in the list the process represents, used to know which
+            neighbor we pass our value to
+value = the initial value at list[position]
+LSend, RSend = the pipes we use to send to our left and right neighbors
+LRcv, RRcv = the pipes we use to receive from our left and right neighbors
+resultPipe = the pipe used to send results back to main
+"""
+
+
+def oe_process(
+    position,
+    value,
+    l_send,
+    r_send,
+    lr_cv,
+    rr_cv,
+    result_pipe,
+    multiprocessing_context,
+    phases: int,
+) -> None:
+    process_lock = multiprocessing_context.Lock()
+
+    # we perform n swaps since after n swaps we know we are sorted
+    # we *could* stop early if we are sorted already, but it takes as long to
+    # find out we are sorted as it does to sort the list with this algorithm
+    for i in range(phases):
+        if (i + position) % 2 == 0 and r_send is not None:
+            # send your value to your right neighbor
+            with process_lock:
+                r_send[1].send(value)
+
+            # receive your right neighbor's value
+            with process_lock:
+                temp = rr_cv[0].recv()
+
+            # take the lower value since you are on the left
+            value = min(value, temp)
+        elif (i + position) % 2 != 0 and l_send is not None:
+            # send your value to your left neighbor
+            with process_lock:
+                l_send[1].send(value)
+
+            # receive your left neighbor's value
+            with process_lock:
+                temp = lr_cv[0].recv()
+
+            # take the higher value since you are on the right
+            value = max(value, temp)
+    # after all swaps are performed, send the values back to main
+    result_pipe[1].send(value)
+
+
+"""
+the function which creates the processes that perform the parallel swaps
+
+arr = the list to be sorted
+"""
+
+
+def odd_even_transposition(arr):
+    """
+    >>> odd_even_transposition(list(range(10)[::-1])) == sorted(list(range(10)[::-1]))
+    True
+    >>> odd_even_transposition(["a", "x", "c"]) == sorted(["x", "a", "c"])
+    True
+    >>> odd_even_transposition([1.9, 42.0, 2.8]) == sorted([1.9, 42.0, 2.8])
+    True
+    >>> odd_even_transposition([False, True, False]) == sorted([False, False, True])
+    True
+    >>> odd_even_transposition([1, 32.0, 9]) == sorted([False, False, True])
+    False
+    >>> odd_even_transposition([1, 32.0, 9]) == sorted([1.0, 32, 9.0])
+    True
+    >>> unsorted_list = [-442, -98, -554, 266, -491, 985, -53, -529, 82, -429]
+    >>> odd_even_transposition(unsorted_list) == sorted(unsorted_list)
+    True
+    >>> unsorted_list = [-442, -98, -554, 266, -491, 985, -53, -529, 82, -429]
+    >>> odd_even_transposition(unsorted_list) == sorted(unsorted_list + [1])
+    False
+    """
+    # spawn method is considered safer than fork
+    multiprocessing_context = mp.get_context("spawn")
+
+    process_array_ = []
+    result_pipe = []
+    # initialize the list of pipes where the values will be retrieved
+    for _ in arr:
+        result_pipe.append(multiprocessing_context.Pipe())
+    # creates the processes
+    # the first and last process only have one neighbor so they are made outside
+    # of the loop
+    temp_rs = multiprocessing_context.Pipe()
+    temp_rr = multiprocessing_context.Pipe()
+    process_array_.append(
+        multiprocessing_context.Process(
+            target=oe_process,
+            args=(
+                0,
+                arr[0],
+                None,
+                temp_rs,
+                None,
+                temp_rr,
+                result_pipe[0],
+                multiprocessing_context,
+                len(arr),
+            ),
+        )
+    )
+    temp_lr = temp_rs
+    temp_ls = temp_rr
+
+    for i in range(1, len(arr) - 1):
+        temp_rs = multiprocessing_context.Pipe()
+        temp_rr = multiprocessing_context.Pipe()
+        process_array_.append(
+            multiprocessing_context.Process(
+                target=oe_process,
+                args=(
+                    i,
+                    arr[i],
+                    temp_ls,
+                    temp_rs,
+                    temp_lr,
+                    temp_rr,
+                    result_pipe[i],
+                    multiprocessing_context,
+                    len(arr),
+                ),
+            )
+        )
+        temp_lr = temp_rs
+        temp_ls = temp_rr
+
+    process_array_.append(
+        multiprocessing_context.Process(
+            target=oe_process,
+            args=(
+                len(arr) - 1,
+                arr[len(arr) - 1],
+                temp_ls,
+                None,
+                temp_lr,
+                None,
+                result_pipe[len(arr) - 1],
+                multiprocessing_context,
+                len(arr),
+            ),
+        )
+    )
+
+    # start the processes
+    for p in process_array_:
+        p.start()
+
+    # wait for the processes to end and write their values to the list
+    for p in range(len(result_pipe)):
+        arr[p] = result_pipe[p][0].recv()
+        process_array_[p].join()
+    return arr
+
+
+# creates a reverse sorted list and sorts it
+def main() -> None:
+    arr = list(range(10, 0, -1))
+    print("Initial List")
+    print(*arr)
+    arr = odd_even_transposition(arr)
+    print("Sorted List\n")
+    print(*arr)
+
+
+if __name__ == "__main__":
+    main()