1 files changed, 64 insertions, 0 deletions
diff --git a/reverse-heap-sort.py b/reverse-heap-sort.py
new file mode 100755
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+++ b/reverse-heap-sort.py
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+#!/bin/python3
+
+# ---------- Heap Sort Algorithm
+# 
+
+
+# ---------- Imported modules
+import inputoutput as io
+import csv
+import sys
+
+
+# ---------- Main
+target = sys.argv[1]
+
+# ingress of data
+numdata = io.ingressCSV(target)
+
+
+# Heap function (set up for algorithm)
+def heapMake(data, node, root):
+    
+    # create root and define left and right tree branches
+    maxi = root
+    left = 2 * root + 1
+    rite = 2 * root + 2
+
+    # check for existence of left child and if so, compare to root
+    if left < node and data[maxi] > data[left]:#FIXME: swapped second comparators to <
+        maxi = left
+
+    # check for existence of right child and if so, compare to root
+    if rite < node and data[maxi] > data[rite]:#FIXME: swapped second compatarors to <
+        maxi = rite
+
+    # if needed change out root value using a swap assignment
+    if maxi != root:
+        data[root], data[maxi] = data[maxi], data[root]
+
+        # recursively make root into a heap
+        heapMake(data, node, maxi)
+
+
+# Algorithm
+def heapSort(atad):
+    span = len(atad)
+
+    # buildup heap
+    for i in range(span // 2 - 1, -1, -1):
+        heapMake(atad, span, i)
+
+    # extract heap elements single-file
+    for i in range(span - 1, 0, -1):
+        # swap assignment
+        atad[i], atad[0] = atad[0], atad[i]
+        heapMake(atad, i, 0)
+
+# using sorting algorithm
+heapSort(numdata)
+
+# finishing up, appending "-heapsorted" to sorted CSV
+target = target[:-4]+"-reverse-heap"+target[-4:]
+print("Sorting done! Writing to file")
+io.egressCSV(numdata,target)