python - 在多维列表中追加项目

Question

我不确定我正在尝试做的这件事情在 Python 中被称为什么，但是如何将项目添加到多维列表中？我知道如何对常规列表执行此操作，并且我试图弄清楚这个数组的内容但完全迷路了。

我想做这样的列表

portfolio_list =[
['TSLA',5000], 
['BA',2000], 
['MSFT',2000], 
['AAPL',1500],
]

我在 while 循环中有这段代码

new_item = input("Add stock ticker > ").upper()
add_to_list(new_item) #adds stock ticker to list 

new_value = input("What is value of {} > ".format(new_item))
add_item_value(new_value)

我对这些的定义是

def add_to_list(item): 
    portfolio_list.append([[item]],axis=0)
    print("{} has been added".format(item,))

def add_item_value(item):
    portfolio_list.append([[item]],axis=1)
    print("{} value has been added to {} ".format(item,new_item))

我得到的错误

Add stock ticker > tsla


Traceback (most recent call last):
  File "test_effecient_frontier.py", line 139, in <module>
    add_to_list(new_item) #adds stock ticker to list
  File "test_effecient_frontier.py", line 70, in add_to_list
    portfolio_list.append([[item]],axis=0)
TypeError: append() takes no keyword arguments

非常感谢任何帮助!

Answer 1

你可以

1. 询问这两种信息
2. append 新的子列表到主 list，不要忘记转换为 int

portfolio_list = [
    ['TSLA', 5000],
    ['BA', 2000],
    ['MSFT', 2000],
    ['AAPL', 1500],
]

new_item = input("Add stock ticker > ").upper()
new_value = input("What is value of {} > ".format(new_item))
portfolio_list.append([new_item, int(new_value)])

通过 while 循环，你可以有类似的想法

while True:
    new_item = input("Add stock ticker > ").upper()
    if new_item == "STOP":
        break
    new_value = input("What is value of {} > ".format(new_item))
    portfolio_list.append([new_item, int(new_value)])