python实现在无须过多援引的情况下创建字典的方法,python援引


本文实例讲述了python实现在无须过多援引的情况下创建字典的方法。分享给大家供大家参考。具体实现方法如下:

1.使用itertools模块

import itertools
the_key = ['ab','22',33]
the_vale = ['aaaa',"dddddddd",'22222222222']
d = dict(itertools.izip(the_key,the_vale))
print d

2.加参数

dict = dict(red = 1,bule = 2,yellow = 3)
print dict

结果为:{'yellow': 3, 'bule': 2, 'red': 1}

3.使用内置的zip函数
zip([iterable,...])返回一个列表,

the_key = ['ab','22',33]
the_vale = ['aaaa',"dddddddd",'22222222222']
dict2 = dict(zip(the_key,the_vale))
print type(zip(the_key,the_vale))
print dict2

结果:

<type 'list'>
{33: '22222222222', 'ab': 'aaaa', '22': 'dddddddd'}

4.dict的fromkeys函数
创建的每个键有相同的value

fromkeys(seq[,value])
Create a new dictionary with keys from seq and values set to value.

the_key = ['ab','22',33]
the_vale = 0
d = dict.fromkeys(the_key,the_vale)
print 

结果:{33: 0, 'ab': 0, '22': 0}

import string
count_by_letter = dict.fromkeys(string.ascii_lowercase,0)
print count_by_letter

结果:

{'a': 0, 'c': 0, 'b': 0, 'e': 0, 'd': 0, 'g': 0, 'f': 0, 'i': 0, 'h': 0, 'k': 0, 'j': 0, 'm': 0, 'l': 0, 'o': 0, 'n': 0, 'q': 0, 'p': 0, 's': 0, 'r': 0, 'u': 0, 't': 0, 'w': 0, 'v': 0, 'y': 0, 'x': 0, 'z': 0}

希望本文所述对大家Python程序设计的学习有所帮助。


python字典中怎创建字典

创建临时的变量
tmp = dict()
tmp.setdefault('b1','abc')
ab['a3']=tmp
 

哪个字典方法可以把两个字典连接在一起 python

有个update()方法,不过如果key相同的话,会用后者的key-value覆盖前者的。

D.update(E, **F) -> None. Update D from dict/iterable E and F.
If E has a .keys() method, does: for k in E: D[k] = E[k]
If E lacks .keys() method, does: for (k, v) in E: D[k] = v
In either case, this is followed by: for k in F: D[k] = F[k]

例子:
>>> a = {3: 5, 4: 6}
>>> b = {4: 8, 7: 9}
>>> a.update(b)
>>> a
{3: 5, 4: 8, 7: 9}
 

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