How to call map function in python3

How to call the map function in python3?

The map function calling syntax in python3:

map(function, iterable, ...)

The python source code is explained as follows:

map(func, *iterables) --> map object
Make an iterator that computes the function using arguments from
each of the iterables.  Stops when the shortest iterable is exhausted.

Simply put,

map() receives A function f and an iterable object (here understood as a list), and by applying the function f to each element of the list in turn, a new list is obtained and returned.

For example, for list [1, 2, 3, 4, 5, 6, 7, 8, 9]

If you want to square each element of the list, you can use map() function:

Therefore, we only need to pass in the function f(x)=x*x, and then we can use the map() function to complete this calculation:

def f(x):
    return x*x
print(list(map(f, [1, 2, 3, 4, 5, 6, 7, 8, 9])))

Output result:

[1, 4, 9, 10, 25, 36, 49, 64, 81]

Use with anonymous functions:

data = list(range(10))
print(list(map(lambda x: x * x, data)))
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

Note: The map() function does not change the original list, but returns a new list.

Using the map() function, you can convert a list into another list by passing in the conversion function.

Since the elements contained in the list can be of any type, map() can not only handle lists containing only numerical values, in fact it can handle lists containing any type, as long as the incoming function f can handle it this data type.

Task

Assuming that the English name entered by the user is not standardized and does not follow the rules of capitalizing the first letter and lowercase subsequent letters, please use the map() function to convert a list (including several non-standard names) English name) into a list containing standardized English names:

def f(s):
    return s[0:1].upper() + s[1:].lower()
list_ = ['lll', 'lKK', 'wXy']
a = map(f, list_)
print(a)
print(list(a))

Running results:

<map object at 0x000001AD0A334908>
[&#39;Lll&#39;, &#39;Lkk&#39;, &#39;Wxy&#39;]

Related recommendations: "Python Tutorial"

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