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Mastering flat_map in Python with List Comprehension

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Introduction In Python, when working with nested lists or iterables, one common challenge is flattening them into a single list while applying transformations. Many programming languages provide a built-in flatMap function, but Python does not have an explicit flat_map method. However, Python’s powerful list comprehensions offer an elegant way to achieve the same functionality. This article examines implementation behavior using Python’s list comprehensions and other methods. What is flat_map ? Functional programming  flatMap is a combination of map and flatten . It transforms the collection's element and flattens the resulting nested structure into a single sequence. For example, given a list of lists, flat_map applies a function to each sublist and returns a single flattened list. Example in a Functional Programming Language: List(List(1, 2), List(3, 4)).flatMap(x => x.map(_ * 2)) // Output: List(2, 4, 6, 8) Implementing flat_map in Python Using List Comprehension Python’...
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Unix: How to Write Shell Script Using vi Editor

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Unix Commands
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When you login into UNIX, you are first in the home directory:

$/home:

Then you can issue

 $/home: cd jthomas

Then you come to your own directory:

$/home/jthomas:

How to write your first script:
$/home/jthomas: vi test.sh

Here, you can write your script.
The first line in the script is:

#!/bin/ksh - It denotes which shell you are going to use.

Example:

$vi test.sh

  #!/bin/ksh 
################################################### # 
Written By: Jason Thomas # Purpose: This script was written to show users 
how to develop their first script 
################################################### # Denotes a comment

root

daemon bin sys adm uucp nobody lpd

How to run a script

$ sh test.sh

 Also read: The complete list of UNIX basic commands

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