Trying to make a function which results largest number in the list

Question

Hi I am a beginner in Python, and I am trying to make a function which shows me the largest element in the list. Where I am going wrong?

l = [2,6,9,7,41,4]

def getmax(l):
    assume = l[0]
    for i in range(1,len(l)):
        if l[0] > l[i]:
            assume = l[0]
        else:
            assume = l[i]
    return assume

print(getmax(l))

You shouldn't use `l[0]` in the `if` and `assume = l[0]`. This way you're always comparing/setting against the first index. Anyway, why not just use the [`max`](https://stackoverflow.com/questions/6193498/pythonic-way-to-find-maximum-value-and-its-index-in-a-list) function? — 0stone0, Mar 17 '22 at 15:44
What evidence do you have that you are doing anything wrong, and why won't you share? — Scott Hunter, Mar 17 '22 at 15:45
Does this answer your question? [Python: Function returning highest value in list without max()?](https://stackoverflow.com/q/19469136/6045800) — Tomerikoo, Mar 17 '22 at 15:52

score 3 · Accepted Answer · answered Mar 17 '22 at 15:46

3

This is what you want, I believe:

l = [2,6,9,7,41,4]

def getmax(l):
    assume = l[0]
    for i in range(1,len(l)):
        if l[i] > assume:
            assume = l[i]
    return assume

print(getmax(l))

Output:

answered Mar 17 '22 at 15:46

constantstranger

9,176
2
5
19

I believe what they *really* want is `max(l)` xD – Tomerikoo Mar 17 '22 at 15:49
@Tomerikoo Wish I could use that :p. Thank you @constantstranger! Learning Python rn and stackoverflow community feels like a heaven for newbies like me :)) – John Paul Mar 17 '22 at 15:52
@John Paul Glad to hear this was useful. Do you need any more help with your question? – constantstranger Mar 17 '22 at 15:57
@constantstranger Thanks, I am done with that question, any suggestions/books/websites for practicing questions could be helpful? – John Paul Mar 17 '22 at 16:42
@John Paul For books and tutorials you could start here: and . – constantstranger Mar 17 '22 at 17:06

loki.dev · Answer 2 · 2022-03-17T15:46:54.147

0

hey of course you can use the builtin max function, but that won't be perfect for the purpose.

Your problem is that you always compare against the l[0] element instead of "assume" :).

def getmax(l: list) -> int:
    assume = l[0]
    for number in l[1:]
         if number > assume:
             assume = number
    return assume

As you see, you don't need the else branch, as the number stays the same with same numbers or a lower number :).

The l[1:] might be confusing, but it means: Take everythin from iterable "l" but skip until the first element.

edited Mar 17 '22 at 15:46

answered Mar 17 '22 at 15:45

loki.dev

172
6

1

*"Take everythin from iterable "l" but skip until the first element."* - that is actually confusing... I think it simply means take everything from the second element to the end – Tomerikoo Mar 17 '22 at 15:50
`l[1:]` actually means "create a copy of `l` omitting the first element". It does not just skip the first element in iteration. – khelwood Mar 17 '22 at 15:51
Hi @loki.dev can you explain me a bit about this line `(l: list) -> int:`? – John Paul Mar 17 '22 at 21:24
Hey @JohnPaul - Yes. This is optional typing. It is there to make sure we now what each of these variables contain. With tools like mypy you can check that everything works as intended :) – loki.dev Mar 18 '22 at 16:14

Trying to make a function which results largest number in the list

2 Answers2