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Python map() and lambda() Use Cases and Examples

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 In Python, map() and lambda functions are often used together for functional programming. Here are some examples to illustrate how they work. Python map and lambda top use cases 1. Using map() with lambda The map() function applies a given function to all items in an iterable (like a list) and returns a map object (which can be converted to a list). Example: Doubling Numbers numbers = [ 1 , 2 , 3 , 4 , 5 ] doubled = list ( map ( lambda x: x * 2 , numbers)) print (doubled) # Output: [2, 4, 6, 8, 10] 2. Using map() to Convert Data Types Example: Converting Strings to Integers string_numbers = [ "1" , "2" , "3" , "4" , "5" ] integers = list ( map ( lambda x: int (x), string_numbers)) print (integers) # Output: [1, 2, 3, 4, 5] 3. Using map() with Multiple Iterables You can also use map() with more than one iterable. The lambda function can take multiple arguments. Example: Adding Two Lists Element-wise list1 = [ 1 , 2 , 3 ]
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Vi Editor to Quit use Esc and Colon

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Here are vi editor commands you can use to quit from Vi editor with or without saving your work. These are useful to use in day-to-day work.

w => To Save Your Work
q => To Quit
wq => To Save and Quit
q! => To quit without saving


vi editor also called Visual editor in terms of Unix or Linux or Ubuntu Operating systems. Since all are the same UNIX flavor, and UNIX is the mother of all these operating systems.


Recently many of my friends asked to share some daily use vi editor commands. I am sharing those for your quick reference.

6 Top vi Editor Commands


1. How to Edit a file?

vi filename

This is the first command to use for editing a file.


2. A command to Repeat Previous Command?

Use the UP arrow to repeat the previous command.


3. How to Insert data?

Use insert command to over-type data.


4. How to Save File?

Press Esc
then
:w

5. How to Save and Quit (Exit)?

Press Esc
then
:wq

6 How to quit without Save?

Press Esc
then
:q!

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