Lesson-17: Python Map Function
Python Map Function
The Map () function executes a function specified for each repeatable element. The element is sent to the function as a parameter.
Python Map Function : map(function, repeated)
|function||Function to execute for each element.|
|repeated||An array, collection, or iterator object. You can send as many iterables as you want, just make sure that the function has a parameter for each iterable.|
Let’s say we have a list like this:liste = [1, 4, 5, 4, 2, 9, 10]
Our goal is to calculate the square of each element in this list. For this purpose, we can follow this path:
for i in liste: print(i ** 2) 1 16 25 16 4 81 100
So, as we wanted, we found the square of all the elements. Another way to do this type of operation is to use an embedded function called map (). Look carefully:
>>> def karesi(n): ... return n ** 2 ...
Here we have defined a function that calculates the square of the number n. Now we will apply this function on all elements of the “liste” list:
>>> list(map(karesi, liste)) [1, 16, 25, 16, 4, 81, 100]
def myfunc(a, b): return a + b x = map(myfunc, ('apple', 'banana', 'cherry'), ('orange', 'lemon', 'pineapple')) print(list(x)) EKRAN ÇIKTISI: ['appleorange', 'bananalemon', 'cherrypineapple']
In this example, since the function named myfunc has 2 parameters, there are 2 separate lists in the iterables section of the map. One of these lists is assigned to a and the other to b and goes to the function. As a result, these two values go into the function and are collected. Because there are String values, they are added next to each other and transferred to a separate list.
def toplama(n): return n + n no= (1, 2, 3, 4) sonuç= map(toplama, no) print(list(sonuç)) EKRAN ÇIKTISI: [2, 4, 6, 8]
In this example, no is a tuple, that is, a bunch, and there are 4 numbers in it. the map (toplama, no) function goes to the addition function for each no tuple element and performs operations. We print the result as a list on the screen.