Adding radix sort to the list (OmkarPathak#26)

Author: 6ug

Sorting/Radix_Sort.py

@@ -0,0 +1,43 @@
+# Sorting Type: Radix
+# 
+# Description: Radix sort is a sorting technique that
+# sorts the elements by first grouping the individual
+# digits of same place value. Then, sort the elements
+# according to their increasing/decreasing order.
+
+from math import log10
+from random import randint
+
+def get_num(num, base, pos):
+  return (num // base ** pos) % base
+
+def prefix_sum(array):
+  for i in range(1, len(array)):
+    array[i] = array[i] + array[i-1]
+  return array
+
+def radixsort(l, base=10):
+  passes = int(log10(max(l))+1)
+  output = [0] * len(l)
+
+  for pos in range(passes):
+    count = [0] * base
+
+    for i in l:
+      digit = get_num(i, base, pos)
+      count[digit] +=1
+
+    count = prefix_sum(count)
+
+    for i in reversed(l):
+      digit = get_num(i, base, pos)
+      count[digit] -= 1
+      new_pos = count[digit]
+      output[new_pos] = i
+
+    l = list(output)
+  return output
+
+l = [ randint(1, 99999) for x in range(100) ]
+sorted = radixsort(l)
+print(sorted)