In Python, the map() function is a built-in function that applies a given function to every item in an iterable (like a list, tuple, or dictionary).

Basic Syntax:

Python 
map(function, iterable)

Use code with caution.

Parameters:

  • function: The function to apply to each item in the iterable.  Python Classes in Mumbai
  • iterable: The iterable (e.g., list, tuple, dictionary) whose elements will be passed to the function.

Return Value:

  • A map object, which is an iterator that yields the results of applying the function to each item in the iterable.

Example:

Python 
def square(x):
    return x * x

numbers = [1, 2, 3, 4, 5]
squared_numbers = map(square, numbers)

# Convert the map object to a list for printing
squared_numbers_list = list(squared_numbers)
print(squared_numbers_list)  # Output: [1, 4, 9, 16, 25]

Use code with caution.

In this example:

  1. The square function is defined to calculate the square of a number.
  2. The map() function is used to apply the square function to each element in the numbers list.
  3. The resulting map object is converted to a list for printing.  Python Course in Mumbai

Key points to remember:

  • The map() function returns an iterator, not a list. To get the results as a list, you need to convert the map object using list().
  • The map() function is often used for functional programming style, where you apply a function to a collection of elements.
  • For simple operations, list comprehensions can be a more concise alternative to map().

By understanding the map() function, you can efficiently apply functions to elements in iterables and write more concise and functional Python code.