Input from List (Python) [duplicate] - python

This question already has answers here:
How to extract parameters from a list and pass them to a function call [duplicate]
(3 answers)
Closed 7 years ago.
I have a parameter list which is just inputs separated by commas.
Now that I have a non-empty list, myList[], how do I turn the entries of L into a parameter list?
Example: if want
myList[0], myList[1], myList[2]..., myList[10]
How can I do that? Thank you! Is there anything similar to unpacking?

You can use unpacking with *.
f(*myList)

Related

creating a list from a set modifies the order of the numbers [duplicate]

This question already has answers here:
python order of elements in set
(2 answers)
Why is the order in dictionaries and sets arbitrary?
(5 answers)
Closed 26 days ago.
I have a list a:
a={4941, 4980, 3855, 4763, 4955}
I convert into a list:
b=list(a)
b now becomes [4980, 4955, 4763, 4941, 3855]
Sorry am I missing something? Eventhough set is an unordered structure why should it change the order ? Or is it the list function that is doing this?
Sorry if this is too naive a question! Many thanks.

Pass list items as arguments to method [duplicate]

This question already has answers here:
How to extract parameters from a list and pass them to a function call [duplicate]
(3 answers)
How to split list and pass them as separate parameter?
(4 answers)
Closed 1 year ago.
Assuming i have a method definition like this do_stuff(*arg).
I have a list of values, ['a','b',...]. How best can i pass the values of this list as individual arguments to the do_stuff method as do_stuff('a','b',...) ?
I've unsuccessfully tried using list comprehension - do_stuff([str(value) for value in some_list])
I am hoping i don't have to change do_stuff() to accept a list
Any pointers would be appreciated.
You can pass them using the "*" operator. So an example would be like this:
def multiplyfouritems(a,b,c,d):
return a*b*c*d
multiplyfouritems(*[1,2,3,4])
It's the same syntax, with the *:
do_stuff(*['a','b','c'])

If we can input in list by loop? if yes then how? [duplicate]

This question already has answers here:
How do I gather user numerical input into a list in Python?
(2 answers)
Closed 3 years ago.
how we can input in list by using for loop?
I can just input list by single line input command.
nlist=list(input("enter your list items :"))
nlist=str(input("enter your list items separated by , :")).split(',')

How to pass a list as a function's arguments [duplicate]

This question already has answers here:
Expanding tuples into arguments
(5 answers)
Closed 8 months ago.
If I have a function:
def run(time, message, time_span_pattern):
...
And a list like:
run_args = ['1s', '1 second alarm', <_sre.SRE_Pattern object at 0x100435680>]
How can I pass the list, as separate arguments, to run? Is there a builtin way to do this, or am I forced to reference each element individually and by index?
You're looking for:
run(*run_args)
This is explained in more detail in this StackOverflow answer about the star and double star operator
It's also covered in the python docs

What is opposite of append() function in python? [duplicate]

This question already has answers here:
How do I prepend to a short python list?
(7 answers)
Closed 6 years ago.
Recently I was learning python,and I want to use the function that is opposite of append() function.How can I use the function insert an element in the first position of the list.Thank you!
Prepend doesn't exist, but you can simply use the insert method:
list.insert(0, element)

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