List indices must be integers or slices, not str - Python

Question

I'm using a dictionary to compile data about stocks and such but when I come to reference the gtin code input by the user, i get the error 'List indices must be integers or slices, not str - Python'

This is the only section of code that causes this:

tempStockLvl = [num]['STOCK_LEVEL']  # This is the line the error references
tempStockLvl = int(tempStockLvl)
tempStockLvl = tempStockLvl - quantity
stock[num]['STOCK_LEVEL'] = tempStockLvl

Error:

File "E:\Computer Science\CODE FINAL v2.py", line 206, in subtractQuant tempStockLvl = [num]['STOCK_LEVEL'] TypeError: list indices must be integers or slices, not str

Thanks in advance to anyone who answers :D

`[num]['STOCK_LEVEL']` - were you trying to index some sort of nested data structure? `something[num]['STOCK_LEVEL']`? — user2357112, May 10 '17 at 18:32
@user2357112 It's a dictionary, and in the dictionary you use the gtin code to find out what data matches the code — AntsOfTheSky, May 10 '17 at 18:33
@AndrewLi i expected the stock level stored in the dictionary about that gtin code to be assigned to the new variable — AntsOfTheSky, May 10 '17 at 18:34
"It's a dictionary" - whatever "it" is, you seem to have entirely forgotten to include it anywhere in this code. — user2357112, May 10 '17 at 18:34
Also, the code you posted is clearly not the same as the code the error message is coming from. — user2357112, May 10 '17 at 18:35
Same problem: the object is missing (probably just `stock`). — handle, May 10 '17 at 18:38
Try changing ```tempStockLvl = [num]['STOCK_LEVEL']``` to ```tempStockLvl = stock[num]['STOCK_LEVEL']``` - what happens then — wwii, May 10 '17 at 18:57

handle · Accepted Answer · 2017-05-10T18:35:09.703

1

You're creating a List with num as the only element, so it's clear it can't be accessed by anything other than index [0].

>>> num = 123
>>> l = [num]
>>> l
[123]
>>> l[0]
123
>>> [123]['anything']
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: list indices must be integers, not str
>>>

Did you mean to write tempStockLvl = stock[num]['STOCK_LEVEL']?

edited May 10 '17 at 18:35

answered May 10 '17 at 18:32

handle

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It's not a list, it references a dictionary (or tries to) – AntsOfTheSky May 10 '17 at 18:35
@Heather Do you know about [accepting an answer](http://stackoverflow.com/help/accepted-answer)? – handle May 11 '17 at 06:42

List indices must be integers or slices, not str - Python

1 Answers1