What do parameters in my specific function mean?
Question:
Im currently solving an algorithmic task with Python and I got this function, which I should finish:
def solution(nums: Union[List[int], Tuple[int, ...]]) -> int:
I don’t understand what does those thing mean in function. What is nums:? What does nums: Union[List[int], Tuple[int, ...]] mean at all. Could you please describe it? thx in advance
Answers:
Annotations can be added to Python functions to provide additional information about the function’s arguments and return value. Annotations are optional, but they can help you understand the purpose of a function, document its behavior, and spot potential errors.
The function solution in your code takes one argument, nums, which is annotated as follows:
nums: Union[List[int], Tuple[int, ...]]
-
nums: This is the name of the parameter.
-
Union: This is a type hinting feature in Python that allows you to specify a type that can be one of several types. In this case, the type of nums can be either a List[int] or a Tuple[int, ...]. The | symbol can also be used instead of Union (starting in Python 3.9).
-
List[int]: This is a type hint for a list of integers. It means that nums can be a list of integers.
-
Tuple[int, ...]: This is a type hint for a tuple of integers. The ... notation is used to indicate that the tuple can contain an arbitrary number of elements, all of which must be integers.
This part:
-> int
specifies the return type of the function. In this case, the function returns an integer.
Basically that’s what we called in Python "Hints". As you don’t need to specify the type in Python, this will help you to know which type is the upcoming value to the function.
To know more about Typing Hints, I recommend you to check out this
nums is the name of the parameter (this is the name that the argument value will be bound to inside your function), and Union[List[int], Tuple[int, ...]] is a type annotation saying that nums is expected to be either a list or a tuple of ints. (A better/simpler way to write this would probably be Sequence[int], although that’s not strictly equivalent, and if the union type was specified as part of the assignment you shouldn’t "correct" your instructor even though in real life you probably wouldn’t specify a type like that.)
The -> int means that the function is expected to return an int.
In other words, the function definition and type annotations are telling you to expect that somebody will call your function with some number of ints, like this:
result = solution([1, 2, 3, 4])
and that you should return an int value, which in the above example would be bound to result.
Im currently solving an algorithmic task with Python and I got this function, which I should finish:
def solution(nums: Union[List[int], Tuple[int, ...]]) -> int:
I don’t understand what does those thing mean in function. What is nums:? What does nums: Union[List[int], Tuple[int, ...]] mean at all. Could you please describe it? thx in advance
Annotations can be added to Python functions to provide additional information about the function’s arguments and return value. Annotations are optional, but they can help you understand the purpose of a function, document its behavior, and spot potential errors.
The function solution in your code takes one argument, nums, which is annotated as follows:
nums: Union[List[int], Tuple[int, ...]]
-
nums: This is the name of the parameter. -
Union: This is a type hinting feature in Python that allows you to specify a type that can be one of several types. In this case, the type of nums can be either aList[int]or aTuple[int, ...]. The|symbol can also be used instead ofUnion(starting in Python 3.9). -
List[int]: This is a type hint for a list of integers. It means thatnumscan be a list of integers. -
Tuple[int, ...]: This is a type hint for a tuple of integers. The...notation is used to indicate that the tuple can contain an arbitrary number of elements, all of which must be integers.
This part:
-> int
specifies the return type of the function. In this case, the function returns an integer.
Basically that’s what we called in Python "Hints". As you don’t need to specify the type in Python, this will help you to know which type is the upcoming value to the function.
To know more about Typing Hints, I recommend you to check out this
nums is the name of the parameter (this is the name that the argument value will be bound to inside your function), and Union[List[int], Tuple[int, ...]] is a type annotation saying that nums is expected to be either a list or a tuple of ints. (A better/simpler way to write this would probably be Sequence[int], although that’s not strictly equivalent, and if the union type was specified as part of the assignment you shouldn’t "correct" your instructor even though in real life you probably wouldn’t specify a type like that.)
The -> int means that the function is expected to return an int.
In other words, the function definition and type annotations are telling you to expect that somebody will call your function with some number of ints, like this:
result = solution([1, 2, 3, 4])
and that you should return an int value, which in the above example would be bound to result.