Python Module learning data structure--collections.counter

Python contains very many standard data structures, such as list,tuple,dict and set, which are built-in types. In addition to these basic built-in types. Python's collections modules are also implemented in a variety of data structures.

Collections----Container data type module

Python version: 2.6 and later versions

The collections module contains data types other than the built-in internal list,dict and tuple.

1.1 Counter

1.1.1 Counter as a container (what is a container, can be loaded into different objects is the container), you can track the number of times the same data.

The initialization input object can be:

1 can be a list

2 Dictionaries

3 Expressions for key parameters

Code:

Import Collectionsprint Collections. Counter (list[' Abcdaa ')) print collections. Counter ({' A ': 1, ' B ': 2, ' C ': 3}) Print collections. Counter (a=2,b=3,c=1)

The result is:

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1.1.2 Constructs a Counter object (this resembles a Dictionary object):

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1.1.3 the number of times each element is accessed:

#!/usr/bin/env python#coding=utf8import COLLECTIONSC = collections. Counter (' Abcdaab ') for letter in ' ABCDE ': print '%s:%d '% (Letter,c[letter])

Just remember this counter return is also a dictionary-like object is OK, the other way you can slowly work in the exploration of learning.

This article is from the blog of "Kun-brother", please make sure to keep this source http://kunge.blog.51cto.com/976628/1559092

Python Module learning data structure--collections.counter