Add an item to the end of the list. Equivalent to a[len(a):] = [x].本方法是添加一个元素到列表末，相当于a[len(a):] = [x]list.extend(iterable)Extend the list by appending all the items from the iterable. Equivalent to a[len
Add an item to the end of the list; equivalent toa[len(a):]=[x]. list.extend(L) Extend the list by appending all the items in the given list; equivalent toa[len(a):]=L. list.insert(i,x) Insert an item at a given position. The first argument is the index of the element bef...
What happens here is that .append() adds the tuple object y to the end of your target list, x. What if you want to add each item in y to the end of x as an individual item and get [1, 2, 3, 4, 5, 6]? In that case, you can use .extend(): Python >>> x = [1,...
•chain将多个迭代器串联起来,形成一个长迭代器: list1 = [1, 2, 3] list2 = ['a', 'b', 'c'] from itertools import chain for item in chain(list1, list2): print(item) 输出: 1 2 3 a b c2.3.2 使用itertools模块实现复杂迭代模式 Python标准库中的itertools模块提供了丰富的迭代器生成...
extend_numbers = [1, 4]# add all elements of numbers to before the extend_numbers list extend_numbers.extend(numbers)print('List after extend():', numbers)# Output: List after extend(): [1, 4, 2, 3, 5] 3.insert():在定义的索引处插入一个项目。
= '\n':self.position -= 1if self.position == 0:# Got to beginning of file before newlinebreakdef end(self):while self.position < len(self.document.characters) and \self.document.characters[self.position].character != '\n':self.position += 1...
DataFrame.itertuples([index, name]) #Iterate over DataFrame rows as namedtuples, with index value as first element of the tuple. DataFrame.lookup(row_labels, col_labels) #Label-based “fancy indexing” function for DataFrame. DataFrame.pop(item) #返回删除的项目 ...
enumerate>>>a=['a','b','c','d','e']>>>forindex,iteminenumerate(a):printindex,item......
update()GLOBAL=b'c'# push self.find_class(modname, name); 2 string argsDICT=b'd'# build a dict from stack itemsEMPTY_DICT=b'}'# push empty dictAPPENDS=b'e'# extend list on stack by topmost stack sliceGET=b'g'# push item from memo on stack; index is string argBINGET=b'h'#...
Before the beginning of every iteration, the next item provided by the iterator (range(4) in this case) is unpacked and assigned the target list variables (i in this case). The enumerate(some_string) function yields a new value i (a counter going up) and a character from the some_...