You can also make a copy of a list by using the : (slice) operator.Example Make a copy of a list with the : operator: thislist = ["apple", "banana", "cherry"] mylist = thislist[:]print(mylist) Try it Yourself »
Return a shallow copy of the list. Equivalent toa[:].所以应该用 importcopytemp_data=[]temp_dat...
However, this still does not copy all inner elements for nested Lists! We only created a so-calledshallow copy. Let's say we have a List of Lists. If we make a copy with one of the above methods and change the inner elements, it still affects the other List as well: a=[[1,2],...
A = copy.copy(B) 此时A对象相当于把B对象中的内容给完成的拷贝了一份,存储在了一份新的内存地址当中。 其中有一点需要注意,如下: 1 import copy 2 3 name = ['root','admin',['root_temp','admin_temp']] 4 cp_name = copy.copy(name) 5 # 查看两个对象的地址 6 print(id(name),id(cp_na...
Return a deep copy of the list. Input: {"$id":"1","next":{"$id":"2","next":null,"random":{"$ref":"2"},"val":2},"random":{"$ref":"2"},"val":1} Explanation: Node 1's value is 1, both of its next and random pointer points to Node 2. ...
def copy(self, *args, **kwargs): # real signature unknown """ Return a shallow copy of the list. """ pass 已经写的很清楚,这是浅拷贝 方式四:使用 copy 模块的 copy 方法 列表 # 浅拷贝 copy模块的copy方法-列表 from copy import copy old_list = [1, 2, [3, 4]] new_list = copy...
Welcome to the sixth installment of the How to Python series. Today, we’re going to learn how to clone or copy a list in Python. Unlike most articles in this series, there are actually quite a few options—some better than others. ...
这里可以看到深拷贝的命令需要import copy,然后调用copy.deepcopy()(真·深拷贝) 程序解读: 开辟空间A存放[11,22,33],然后将其地址放在a中,在执行b = copy.deepcopy(a)后,py君又开辟了新空间B,直接将原来A空间里的[11,22,33]拿了过来放到B空间中,然后把B控件的地址给了b。这样就完成了深拷贝。
Python提供了5中内置的序列类型:bytearray、bytes、list、str与tuple,序列类型支持成员关系操作符(in)、大小计算函数(len())、分片([]),并且是可可迭代的。 1.1 元组 元组是个有序序列,包含0个或多个对象引用,使用小括号包裹。元组是固定的,不能替换或删除其中包含的任意数据项。
list.copy():列表浅拷贝,也就是说,只拷贝父对象,不会拷贝对象内部的子对象 常用操作 列表性质 len(L) #长度 max(L) #最大值 min(L) #最小值 sum(L) # 求和 sum(L)/len(L) # 求均值 for x,y in enumerate(L): #查看索引与值 print(x,y) Tips 深拷贝和浅拷贝问题 对列表的赋值、append 和...