From 7f9cf980f355b87de6ea6c820be9e567e9227439 Mon Sep 17 00:00:00 2001
From: trollhase <valentingehrke@gmx.de>
Date: Sat, 28 Sep 2013 06:12:19 +0200
Subject: [PATCH] Sorting Algorithm Tester
---
sorting_algorithms.py | 199 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 199 insertions(+)
create mode 100644 sorting_algorithms.py
diff --git a/sorting_algorithms.py b/sorting_algorithms.py
new file mode 100644
index 0000000..92d218f
--- /dev/null
+++ b/sorting_algorithms.py
@@ -0,0 +1,199 @@
+
+from random import randint
+from time import clock
+
+class SortAlgorithm:
+ def __init__(self):
+ self.swaps = 0
+ self.vgls = 0
+
+ def sort(self,a):
+ raise Exception("Fail")
+
+ def swap(self,a,i,j):
+ self.swaps += 1
+ a[i],a[j] = a[j],a[i]
+
+ def set(self,a,i,v):
+ self.swaps += 1
+ a[i] = v
+
+ def vgl(self,b):
+ self.vgls += 1
+ return b
+
+class BubbleSort(SortAlgorithm):
+ def sort(self,a):
+ n = len(a)
+ swapped = True
+ while swapped and n > 1:
+ swapped = False
+ for i in range(0,n-1):
+ if self.vgl(a[i] > a[i+1]):
+ self.swap(a,i,i+1)
+ swapped = True
+ n-=1
+ return a
+
+class InsertSort(SortAlgorithm):
+ def sort(self,a):
+ for i in range(1,len(a)):
+ t = a[i]
+ j = i-1
+ while j >= 0 and self.vgl(a[i] > t):
+ self.set(a,j,a[j+1])
+ j-=1
+ #a[j+1] = t
+ self.set(a, j+1, t)
+ return a
+
+class QuickSort(SortAlgorithm):
+ def sort(self,a):
+ self.qsort(a, 0, len(a)-1)
+ return a
+
+ def qsort(self,a, left, right):
+ if left < right:
+ pivot = self.seperate(a, left, right)
+ self.qsort(a, left, pivot - 1)
+ self.qsort(a, pivot+1, right)
+
+ def seperate(self, a, left, right):
+ i = left
+ j = right-1
+ pivot = a[right]
+
+ while i < j:
+ while self.vgl(a[i] <= pivot) and i < right: i+=1
+ while self.vgl(a[i] >= pivot) and j > left: j-=1
+
+ if i < j:
+ self.swap(a,i,j)
+
+ if a[i] > pivot:
+ self.swap(a,i,right)
+
+ return i
+
+class HeapSort(SortAlgorithm):
+ def sort(self,a):
+ self.heapsort(a)
+ return a
+
+ def heapify(self, data, i, w):
+ #indexes = filter(lambda v: v < w, [i,2*(i+1)-1,2*(i+1)])
+ #largest = max(indexes,key=lambda v: data[v])
+ r = 2*(i+1)
+ l = r-1
+ largest = i
+ if l < w and self.vgl(data[l] < data[largest]):
+ largest = l
+ if r < w and self.vgl(data[r] < data[largest]):
+ largest = r
+ if largest != i:
+ self.swap(data,i,largest)
+ self.heapify(data, largest, w)
+
+ def build_heap(self, data):
+ w = len(data)
+ i = w/2-1
+ while i>=0:
+ self.heapify(data, i, w)
+ i-=1
+
+ def heapsort(self,data):
+ self.build_heap(data)
+ i = len(data)-1
+ while i > 0:
+ self.swap(data,i,0)
+ self.heapify(data, 0, i)
+ i-=1
+
+class MergeSort(SortAlgorithm):
+ def sort(self, a):
+ return self.mergesort(a)
+
+ def mergesort(self,a):
+ if len(a) <= 1:
+ return a
+ else:
+ n = len(a)/2
+ return self.merge(self.mergesort(a[:n] or []), self.mergesort(a[n:] or []))
+
+ def merge(self,a,b):
+ l = []
+ while True:
+ if len(a) == 0:
+ l += b
+ break
+ if len(b) == 0:
+ l += a
+ break
+
+ if self.vgl(a[0] < b[0]):
+ l.append(a[0])
+ a = a[1:]
+ else:
+ l.append(b[0])
+ b = b[1:]
+ self.swaps+=1
+ return l
+
+class ShellSort(SortAlgorithm):
+ def sort(self,a):
+ spalten = [2147483647, 1131376761, 410151271, 157840433, 58548857, 21521774, 8810089, 3501671, 1355339, 543749, 213331,
+ 84801, 27901, 11969, 4711, 1968, 815, 271, 111, 41, 13, 4, 1]
+
+ for k in range(0,23):
+ h = spalten[k]
+ for i in range(h,len(a)):
+ t = a[i]
+ j = i
+ while j>=h and self.vgl(a[j-h]>t):
+ #a[j] = a[j-h]
+ self.swap(a,j,j-h)
+ j-=h
+ a[j] = t
+ return a
+
+class SelectSort(SortAlgorithm):
+ def sort(self,a):
+ n = len(a)
+ left = 0
+ while left < n:
+ m = left
+ for i in range(left,n):
+ if self.vgl(a[i] < a[m]):
+ m = i
+ self.swap(a,m,left)
+ left+=1
+ return a
+
+class SortTester:
+ def __init__(self, algorithms):
+ self.algorithms = algorithms
+
+ def test(self, size=1000):
+ results = {}
+
+ data = list([ randint(0, size) for i in range(0,size) ])
+
+ for algorithm in self.algorithms:
+ print "Testing %s..." % algorithm.__name__
+ inst = algorithm()
+ c = data[:]
+ inst.sort(c)
+ results[algorithm] = (inst.vgls,inst.swaps)
+
+ return results
+
+def main():
+ result = SortTester([BubbleSort,InsertSort,QuickSort,HeapSort,MergeSort,ShellSort,SelectSort]).test(size=1000)
+ for cls, r in result.items():
+ print "%-12s: %d compares, %d swaps" % (cls.__name__, r[0],r[1])
+
+def test():
+ print ShellSort().sort([randint(0,500) for i in range(0,100)])
+
+if __name__ == '__main__':
+ main()