importoperator # create tuples with college id # and name and store in a list data=[(1,'sravan'),(2,'ojaswi'), (3,'bobby'),(4,'rohith'), (5,'gnanesh')] # map the data using item # getter method with first elements first_data=map(operator.itemgetter(0),data) # display firs...
ExampleGet your own Python Server Print the second item in the tuple: thistuple = ("apple", "banana", "cherry") print(thistuple[1]) Try it Yourself » Note: The first item has index 0.Negative IndexingNegative indexing means start from the end....
Q.get([block[, timeout]]) 获取队列,timeout等待时间。 Q.get_nowait() 相当于Queue.get(False),非阻塞方法。 Q.put(item) 写入队列,timeout等待时间。 Q.task_done() task_done()调用告诉队列该任务已经处理完毕 Q.join() 实际上意味着等到队列为空,再执行别的操作 FIFO队列 FIFO,即First In First...
my_tuple=(1,'apple',3.14)first_element=my_tuple[0]# 1second_element=my_tuple[1]# 'apple' 切片操作也可以用于获取元组的一部分: slice_of_tuple=my_tuple[1:3]# ('apple', 3.14) 2.3 元组的长度 要获取元组的元素个数,可以使用内置的 len() 函数: length=len(my_tuple)# 3 2.4 元组的遍历 ...
first_student = students[0] # "Alice" last_student = students[-1] # "Charlie"2.1.1.2 列表的增删改操作 列表提供了丰富的内置方法来改变其内容: •增:append()、extend()、insert() •删:remove()、pop()、del关键字、clear() •改:直接赋值或使用list[index] = new_value ...
Omitting the first index starts the slice at the beginning of the list, and omitting the second index extends the slice to the end of the list:省略起止索引数时表示什么? >>> print(a[:4], a[0:4]) ['foo', 'bar', 'baz', 'qux'] ['foo', 'bar', 'baz', 'qux'] >>> print...
<class'tuple'> 2.2 创建空元组 创建空元组 tup1 = () 元组中只包含一个元素时,需要在元素后面添加逗号 ,,否则括号会被当作运算符使用: >>>tup1 = (50)>>>type(tup1)# 不加逗号,类型为整型<class'int'>>>tup1 = (50,)>>>type(tup1)# 加上逗号,类型为元组<class'tuple'> 元组...
ExampleGet your own Python Server Create a Tuple: thistuple = ("apple","banana","cherry") print(thistuple) Try it Yourself » Tuple Items Tuple items are ordered, unchangeable, and allow duplicate values. Tuple items are indexed, the first item has index[0], the second item has index...
Fix the bug in branch B. Commit and (optionally) push to remote. Check out branch A Rungit stash popto get your stashed changes back. Git stash stores the changes you made to the working directory locally (inside your project's .git directory;/.git/refs/stash, to be precise) and all...
ndarray.strides 遍历数组时,每个维度中的字节元组。ndarray.ndim 数组维数。ndarray.dataPython缓冲区对象指向数组的数据的开头。ndarray.size 数组中的元素数。ndarray.itemsize 一个数组元素的长度,以字节为单位ndarray.nbytes 数组元素消耗的总字节数。ndarray.base 如果内存来自某个其他对象,则为基础对象。