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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 Top Commands for Ubuntu OS

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I have given VI editor commands to use in Ubuntu operating system. You can practice using them for your benefit and you can complete your work quickly.

Ubuntu vi editor commands

To begin changing or adding to text with vi, you can enter Insert or Replace modes, as shown in the following list. When you enter Insert or Replace mode, the characters you type will appear in the text document (as opposed to being interpreted as commands). 

vi filename

This is the first command to enter into editor mode. Once you enter into editor mode, you need to enter other commands to complete your editing work.

Press the Esc key to exit to Normal mode after you are done inserting or replacing text.

List of VI Editor Commands..

i—Typed text appears before current character.
a—Typed text appears after current character.
o—Open a new line below current line to begin typing.
s—Erase current character and replace with new text.
c?—Replace ? with l, w, $, or c to change the current letter, word, end of line, or line.
r—Replace current character with the next one you type.
Shift+i—Typed text appears at the beginning of current line.
Shift+a—Typed text appears at the end of current line.
Shift+o—Open a new line above current line to begin typing.
Shift+s—Erase current line and enter new text.
Shift+c—Erase from cursor to end of line and enter new text.
Shift+r—Overwrite as you type from current character going forward.

Shortcut keys to delete or paste


x—Delete text under cursor.
d?—Replace ? with l, w, $, or d to cut the current letter, word, or end of line from cursor or entire line.
y?—Replace ? with l, w, or $ to copy (yank) the current letter, word, or end of line from cursor.
p—Pastes cut or yanked text after cursor.
Shift+x—Delete text to left of cursor.
Shift+d—Cut from cursor to end of line.
Shift+y—Yank current line .
Shift+p—Pastes cut or yanked text before cursor.

How to Save VI editor changes...

Press - Esc key
:x
Press Enter
Your work will be saved.


Summary

The above commands useful to work with VI editor. You can complete your task quickly and saves lot of time.

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