Python中字典排序

如字典dic={'a':1,'f':2,'c':3,'h':0};要对其进行排序:

函数原型:sorted(dic,value,reverse);

1. dic为比较函数;
2. value为比较对象(键或值);
3. reverse：注明升序还是降序,True--降序,False--升序（默认）;

    1 import operator;    
    2 # 字典中排序
    3 def sortDict():
    4     dic={'a':1,'f':2,'c':3,'h':0};
    5     # 函数原型：sorted(dic,value,reverse)
    6     # 按字典中的键进行升序排序
    7     print("按键进行升序排序结果为:",\
    8           sorted(dic.items(),key=operator.itemgetter(0),reverse=False));
    9     # 按字典中的键进行降序排序
   10     print("按键进行降序排序结果为:",\
   11           sorted(dic.items(),key=operator.itemgetter(0),reverse=True));
   12     # 按字典中的值进行升序排序
   13     print("按值进行升序排序结果为:",\
   14           sorted(dic.items(),key=operator.itemgetter(1),reverse=False));
   15     # 按字典中的值进行降序排序
   16     print("按值进行降序排序结果为:",\
   17           sorted(dic.items(),key=operator.itemgetter(1),reverse=True));

   运行结果为:

   1 >>> import randMatrix;
   2 >>> sortDict()
   3 按键进行升序排序结果为: [('a', 1), ('c', 3), ('f', 2), ('h', 0)]
   4 按键进行降序排序结果为: [('h', 0), ('f', 2), ('c', 3), ('a', 1)]
   5 按值进行升序排序结果为: [('h', 0), ('a', 1), ('f', 2), ('c', 3)]
   6 按值进行降序排序结果为: [('c', 3), ('f', 2), ('a', 1), ('h', 0)]

   iteritems()函数:

• iteritems()以迭代器对象返回字典键值对;

• 和item相比:items以列表形式返回字典键值对

   1 >>> dic={'a':1,'f':2,'c':3,'h':0};
   2 >>> dic.items()
   3 dict_items([('f', 2), ('h', 0), ('c', 3), ('a', 1)])
   4 >>> dic.iteritems()
   5 Traceback (most recent call last):
   6   File "<pyshell#34>", line 1, in <module>
   7     dic.iteritems()
   8 AttributeError: 'dict' object has no attribute 'iteritems'
   9 >>> print(dic.iteritems())
  10 Traceback (most recent call last):
  11   File "<pyshell#35>", line 1, in <module>
  12     print(dic.iteritems())
  13 AttributeError: 'dict' object has no attribute 'iteritems'

  在Python3.4.2中没有iteritems()函数,所以报错;