1.3数据类型（tuple）

元祖创建

元祖创建简单，只需在括号中添加元素，元素间用逗号隔开，元祖元素不可修改，例子：

>>> tuple1 = ("hello","world",1970,1999)
>>> tuple1
('hello', 'world', 1970, 1999)

创建空元祖，例子：

>>> tuple1 = ()
>>> tuple1
()

元祖中只包含一个元素时，需在元素后面添加逗号，例子：

>>> tuple1 = (50,)
>>> tuple1
(50,)

元祖访问

元祖使用下标索引访问元祖中元素，例子:

例一：

>>> tuple1 = ("hello","world",1970,1999)

>>> tuple1[1]
'world'

例二：

>>> tuple1 = ("hello","world",1970,1999)

>>> tuple1[1:3]

('world', 1970)

元祖修改

元祖中的元素不允许修改，可以通过元祖进行连接组合，例子：

例一：

>>> tuple1 = (1,2,3,4,5)
>>> tuple2 = (7,8,9)
>>> tuple3 = tuple1 + tuple2
>>> tuple3
(1, 2, 3, 4, 5, 7, 8, 9)

例二：

>>> tuple1 = (1,2,3,4,5)
>>> tuple2 = (7,8,9)
>>> tuple1 = tuple1[2:4] + tuple2[0:2]
>>> tuple1
(3, 4, 7, 8)
元祖删除

元祖中的元素是不允许删除的，可以通过del删除整个元祖，例子：

>>> tuple1 = (1,2,3,4,5)

>>> del tuple1
>>> tuple1

元祖无关闭分隔符

以逗号分开无关闭的分隔开符的对象，默认为元祖，例子：

def return_tuple(x,y):
return x,y

if __name__ == "__main__":
x = 1
y = 2
return_tuple_value = return_tuple(x,y)
print "return_tuple_value:" + str(return_tuple_value)
print "return_tuple_value type:" + str(type(return_tuple_value))

return_tuple_value:(1, 2)
return_tuple_value type:<type 'tuple'>

元祖运算符：+、*、[]、[:] 、in、for i in tuple_demo

操作符	描述	实例
+	组合	>>> tuple1 = (1,2,3,4,5) >>> tuple2 = (7,8,9) >>> tuple3 = tuple1 + tuple2 >>> tuple3 (1, 2, 3, 4, 5, 7, 8, 9)
*	重复	>>> tuple1 = ("hello","world") >>> tuple1 * 3 ('hello', 'world', 'hello', 'world', 'hello', 'world')
[]	索引	>>> tuple1 = ("hello","world",1970,1999) >>> tuple1[1] 'world'
[:]	截取	>>> tuple1 = ("hello","world",1970,1999) >>> tuple1[1:3] ('world', 1970)
in	成员运算符--元素存在元祖中返回True	>>> tuple1 = (1,2,3,4,5,6) >>> 1 in tuple1 True
not in	成员运算符--元素不存在元祖中返回True	>>> tuple1 = (1,2,3,4,5,6) >>> 7 not in tuple1 True
for in tuple_demo	迭代	>>> tuple1 = (1,2,3,4,5,6) >>> for i in tuple1: print i 1 2 3 4 5 6

元祖函数

语法	描述	参数	返回	实例
cmp(tuple1,tuple2)	比较两个元祖元素	tuple1--比较元祖 tuple2-比较元祖	tuple1 < tuple2：-1 tuple1 > tuple2:1 tuple1 == tuple2:0	>>> tuple1 = (1,2,3) >>> tuple2 = (1,2,3,4) >>> cmp(tuple1,tuple2) -1 >>> cmp(tuple2,tuple1) 1 >>> tuple3 = (1,2,3) >>> cmp(tuple1,tuple3) 0
len(tuple)	计算元祖中元素个数	tuple--需要计算长度的元祖	元祖中元素个数	>>> tuple1 = (1,2,3,4) >>> len(tuple1) 4
max(tuple)	返回元祖中最大的元素	tuple--需要返回最大值元素的元祖	元祖中最大值的元素	>>> tuple1 = (1,2,3,4) >>> max(tuple1) 4
min(tuple)	返回元祖中最小的元素	tuple--需要返回最小值元素的元祖	元祖中最小值的元素	>>> tuple1 = (1,2,3,4) >>> min(tuple1) 1
tuple(seq)	将有序String和list转换成tuple	seq--需要转换成tuple的string或list	返回转换后的元祖	>>> str1 = "hello python!!!" >>> str_tuple = tuple(str1) >>> str_tuple ('h', 'e', 'l', 'l', 'o', ' ', 'p', 'y', 't', 'h', 'o', 'n', '!', '!', '!') >>> list1 = [1,2,3,4,5,6] >>> list_tuple = tuple(list1) >>> list_tuple (1, 2, 3, 4, 5, 6)