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python 列表list初始化

1. 基本方法

   $ python
   Python 3.5.2 (default, Sep 14 2017, 22:51:06) 
   [GCC 5.4.0 20160609] on linux
   Type "help", "copyright", "credits" or "license" for more information.
   >>> n = [1, 2, 3, 4]
   >>> print (n)
   [1, 2, 3, 4]
   >>> 

2. 连续数字初始化

   >>> list1 = [n for n in range(1,6)]
   >>> print list1
    File "<stdin>", line 1
      print list1 #python3 特性输出要()
                ^
   SyntaxError: Missing parentheses in call to 'print'
   >>> print (list1)
   [1, 2, 3, 4, 5]
   >>> 

3. 相同的值初始化

   >>> #第一种方法
   >>> list2 = ['a' for n in range(4)]
   >>> print(list2)
   ['a', 'a', 'a', 'a']
   >>> #第二种方法:字符和数字
   >>> list3 = ['b'] * 4
   >>> print(list3)
   ['b', 'b', 'b', 'b']
   >>> list4 = [3] * 4
   >>> print (list4)
   [3, 3, 3, 3]
   >>> 

4. 二位数组初始化

   $ python
   Python 3.5.2 (default, Sep 14 2017, 22:51:06) 
   [GCC 5.4.0 20160609] on linux
   Type "help", "copyright", "credits" or "license" for more information.
   >>> #初始一个5×4的数组
   >>> multilist = [[1 for col in range(5)] for row in range(4)]
   >>> print (multilist)
   [[1, 1, 1, 1, 1], [1, 1, 1, 1, 1], [1, 1, 1, 1, 1], [1, 1, 1, 1, 1]]
   >>> 

   ​
   
   list 练习