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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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How to Work with 'Pointers' in Python

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Pointers denote an address (memory location). It has three identities - Name, Value, and Location (Address). Python doesn't support pointers as-is. You need to import 'ctypes' package to work with C Language.

Note: Pointer is popular in C, C++. The called module just uses the value of Pointer (not address).  Below is my detailed post on pointers.  


An article on how to work with pointers


How to work with Pointers

  • To pass a reference(address) to the C interface.
  • You can use C Language in Python by importing 'ctypes.' 

Pointer Notation

1. Value
2. Address
3. Name

Python Pointers


Python doesn't support pointers. C and C++ extensively support pointers. Pointer is nothing but an ADDRESS. It is immutable. That means you can't change the value. Python supports pointers for the purpose to interact with C Language.



Pointers

How to Import 'ctypes'

  1. Import 'ctypes' library for the purpose of working with C language. 
  2. Here's how to import 'ctypes' for windows and Linux.

How to denote Pointers

Here's the way to denote pointers in Python. Check out here Python Pointers.

  
from ctypes import * 
i = c_int(42) 
pi = pointer(i)


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