What is a bubble sort good for? [closed]

Question

Do bubble sorts have any real world use? Every time I see one mentioned, it's always either:

1. A sorting algorithm to learn with.
2. An example of a sorting algorithm not to use.

Answer 1

It's good for small data sets - which is why some qsort implementations switch to it when the partition size gets small. But insertion sort is still faster, so there's no good reason to use it except as a teaching aid.

Answer 2

It depends on the way your data is distributed - if you can make some assumptions.

One of the best links I've found to understand when to use a bubble sort - or some other sort, is this - an animated view on sorting algorithms:

http://www.sorting-algorithms.com/

Answer 3

Bubble sort is easy to implement and it is fast enough when you have small data sets.

Bubble sort is fast enough when your set is almost sorted (e.g. one or several elements are not in the correct positions), in this case you better to interlace traverses from 0-index to n-index and from n-index to 0-index. Using C++ it can be implemented in the following way:

void bubbleSort(vector<int>& v) { // sort in ascending order
  bool go = true;
  while (go) {
    go = false;
    for (int i = 0; i+1 < v.size(); ++i)
      if (v[i] > v[i+1]) {
         swap(v[i], v[j]);
         go = true;
      }
    for (int i = (int)v.size()-1; i > 0; --i) 
      if (v[i-1] > v[i]) {
         swap(v[i-1], v[i]);
         go = true;
      }
  }
}

It can be good if swap of two adjacent items is chip and swap of arbitrary items is expensive.

Donald Knuth, in his famous "The Art of Computer Programming", concluded that "the bubble sort seems to have nothing to recommend it, except a catchy name and the fact that it leads to some interesting theoretical problems".

Since this algorithm is easy to implement it is easy to support, and it is important in real application life cycle to reduce effort for support.

Answer 4

It's quick and easy to code and (nearly impossible to do wrong). It has it's place if you're not doing heavy lifting and there's no library sorting support.

Answer 5

Mostly nothing. Use QuickSort or SelectionSort instead...!

Answer 6

Oh yes, it is a good selection mechanism. If you find it in code written by someone, you don't hire him.