Several data structures in the python collection module (Counter, OrderedDict, namedtup)

Several data structures in the python collection module (Counter, OrderedDict, namedtup)

The collection module has several data structures that we may use.

Counter is a sub-class of the dictionary and is responsible for counting a dictionary. It supports + addition, subtraction, and common elements. | calculates the Union set.

 

Print ('counter type application') c = Counter ("dengjingdong") # c = Counter ({'N': 3, 'G': 3, 'D ': 2, 'I': 1, 'O': 1, 'E': 1, 'J': 1}) print ("Raw data:", c) print ("two elements at most:", c. most_common (2) # print ("Number of d:", c ['D']) of the most output elements # print (c. values () # print (sum (c. values () # print (sorted (c. elements () # Sort the data in the dictionary in the lexicographically ordered print ('\ n \ n ') "# Delete All d Elements del c ['D'] B = Counter (" dengxiaoxiao ") # Use the subtract function to delete elements. The number of elements can be negative. C. subtract (B) "You can add data B = Counter (" qinghuabeida ") c. update (B )"""

The OrderedDict type is an ordered dictionary, which is actually an order more than a common dictionary.

 

 

Print ('ordereddict-type application ') dic = {} dic ['a'] = 'A' dic ['B'] = 'B' dic ['C'] = 'C' odic = OrderedDict () odic ['a'] = 'A' odic ['B'] = 'B' odic ['C'] = 'C' print ('unordered dictionary: ', dic) print ('ordered dictionary: ', odic) print (' \ n \ n ')

Namedtup type. A dictionary-like tuples can be converted to dictionaries.

 

 

Print ('namedtup type application') deng = namedtuple ('deng', ['x', 'y']) I = deng (x = 11, y = 12) print ('I value:', I) print ('add two values: ', I [0] + I [1]) print ('add by attribute: ', I. x + I. y) m, n = iprint ('values similar to tuples: ', m, n) d = I. _ asdict () print ('convert to a dictionary: ', d)