How to sort alpha numeric set in python

by

Jeff Atwood talks about natural sort and gives an example of one way to do it in Python. Here is my variation on it:

import re 

def sorted_nicely( l ): 
    """ Sort the given iterable in the way that humans expect.""" 
    convert = lambda text: int(text) if text.isdigit() else text 
    alphanum_key = lambda key: [ convert(c) for c in re.split('([0-9]+)', key) ] 
    return sorted(l, key = alphanum_key)

Use like this:

s = set(['booklet', '4 sheets', '48 sheets', '12 sheets'])
for x in sorted_nicely(s):
    print(x)

Output:

4 sheets
12 sheets
48 sheets
booklet

One advantage of this method is that it doesn’t just work when the strings are separated by spaces. It will also work for other separators such as the period in version numbers (for example 1.9.1 comes before 1.10.0).

More Related Contents:

  1. How do I sort a dictionary by value?
  2. How to sort a list of objects based on an attribute of the objects?
  3. How to sort a dataFrame in python pandas by two or more columns?
  4. how to sort pandas dataframe from one column
  5. Python analog of PHP’s natsort function (sort a list using a “natural order” algorithm) [duplicate]
  6. Rank items in an array using Python/NumPy, without sorting array twice
  7. Sort list of lists ascending and then descending
  8. How to sort a list of lists by a specific index of the inner list?
  9. Combining two sorted lists in Python
  10. Why is Bubble Sort implementation looping forever?
  11. Custom Python list sorting
  12. How can I “zip sort” parallel numpy arrays?
  13. How to sort OrderedDict of OrderedDict?
  14. Find the unique values in a column and then sort them
  15. Sorting a tuple that contains tuples
  16. Python Math – TypeError: ‘NoneType’ object is not subscriptable
  17. Why is the cmp parameter removed from sort/sorted in Python3.0?
  18. Sort filenames in directory in ascending order [duplicate]
  19. Making a python user-defined class sortable, hashable
  20. Sort invariant for numpy.argsort with multiple dimensions
  21. Given parallel lists, how can I sort one while permuting (rearranging) the other in the same way?
  22. Pandas DataFrame sort by categorical column but by specific class ordering
  23. Sort a list of tuples by second value, reverse=True and then by key, reverse=False
  24. Sort list while pushing None values to the end
  25. What arguments does Python sort() function have?
  26. How can I sort a list, according to where its elements appear in another list?
  27. Sort strings by the first N characters
  28. numerical sort a column containing numbers and strings (pandas/python)
  29. Multi Index Sorting in Pandas
  30. Sort array’s rows by another array in Python

Leave a Comment