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Python中是否有list的dict.update(sub_dict)函数?(当列表为空时)_Python_List_Dictionary - Fatal编程技术网

Python中是否有list的dict.update(sub_dict)函数?(当列表为空时)

Python中是否有list的dict.update(sub_dict)函数?(当列表为空时),python,list,dictionary,Python,List,Dictionary,假设Python->mylist中有一个列表: mylist = [] 现在,我想从用户处获取输入,并在mylist中更新之后的值: input1 = ["xyz","wyh",34] print mylist Output: [["xyz","wyh",34]] input2 = ["yo","hey",657] print mylist output: [["xyz","wyh",34],["yo","hey",657]] 仅当列表中已有某些值时,“附加”才起作用。您可以使用 我建议你

假设Python->mylist中有一个列表:

mylist = []
现在,我想从用户处获取输入,并在mylist中更新之后的值:

input1 = ["xyz","wyh",34]
print mylist
Output: [["xyz","wyh",34]]

input2 = ["yo","hey",657]
print mylist
output: [["xyz","wyh",34],["yo","hey",657]]
仅当列表中已有某些值时,“附加”才起作用。

您可以使用


我建议你仔细看看你到底需要什么。听起来你想要的是list.append

mylist = [["X","Y",12], ["A","B",23]]
mylist.append(["L","M",56])

... list.append?是的,我不确定混淆的地方是什么…也许我们应该链接文档?你可能想用或标记问题。可能的重复项我也会标记它,但我没有更多的标记:谈论低努力的答案-\u-如果列表值为空,那么它将不会追加。在这种情况下会发生什么?如果没有任何初始值,则应首先使用mylist=[]初始化列表。Append将在任何列表上工作,即使它是空的
mylist = [["X","Y",12], ["A","B",23]]
mylist.append(["L","M",56])