map(float, input().split())

This line of code takes input from the user in the form of space-separated values and converts them into floating-point numbers using the built-in function `map()`.

The `map()` function takes two arguments: the first argument is a function (in this case `float`) that will be applied to each element in the second argument, which is an iterable (in this case the user input that has been split into a list). The function returns an iterator that can be converted into a list or used in a loop.

So, if the user enters something like "3.14 2.718 1.618", the code will convert each of those values to a float and return an iterator that can be used to access those values. For example:

>>> values = map(float, input().split())
3.14 2.718 1.618
>>> print(list(values))
[3.14, 2.718, 1.618]

This could be useful for processing numerical input from the user, such as in a scientific computing or data analysis application.