June | 2021 | Ali's Photography Space...

Python: Sorting Algorithm (3. Merge Sort)

June 3, 2021 Ali Radwani 3 comments

Learning : Python coding, Math, Algorithm,
Subject: Writing Merge Sorting Algorithm in Python

[NOTE: To keep the code as simple as we can, We WILL NOT ADD any user input Varevecations. Assuming that our user will Enter the right inputs.]

Sorting Algorithm is a way to sort a given list/Array of numbers, there are several sorting Algorithm as follow:
Type of Sorting Algorithm
1. Quick Sort. [Click Here]
2. Bubble Sort. [Click Here]
3. Merge Sort. [Click Here]
4. Insertion Sort. [Click Here]
5. Selection Sort. [Click Here]
6. Heap Sort. [Click Here]
7. Radix Sort. [Click Here]
8. Bucket Sort. [Click Here]

Here in this post we will write a function to take a given list and sort it then pass it back. We assume the user will enter a serial of numbers, that he want to sort, our function will sort it and print out the original numbers and the sorted one.

Merge Sort: Steps of Merge Sorting Algorithm are:

1. If the Array has 1 Element then return it.
2. If the givin Array has more than 1 Element then we Divide it into 2 Parts.
Left = from Element 0 T0 Element len(arr)//2
and Right = from Element len(arr)//2 To Element len(arr). And we keep repeating step 2 for each part.
3. Once we have All parts divided we tart merge them in a sorted order.

Coding: In this Post we will write the Function for Main-Mnu, another one to collect the Array [Not Sorted] Elements from the user, then we will write the Main Function, here we will have One to Divide the Array into parts and One to Merge the Element together again. And as we done with Quick & Bubble Sort projects we will have one Fast-Run Function and another one with Details Step-By-Step run to show the Algorithm.

NOTE: All the Code will be Available in the Download Page.

Let’s start with the Main-menu to list down three option were the user will select one among them, the menu options are: 1. Merge Sort Algorithm – Fast Run. & 2. Merge Sort Algorithm – Step By Step and the last one is 3. Exit.
Here is the code.

python code project main menu by Ali Radwani merge sort Algorithm

I will Not post the code for collecting the Array Element from the user [Find it in the .py file for this project]. Here is the code for merge_sort_divider Function, it takes two arguments the Array and the user_selection, so if the user selection is 2 (2. Merge Sort Algorithm – Step By Step) We will print-out the Dividing Steps and some other Text. [We are using If Statement to print-out Text lines]. Here is the Code ..

ali radwani python code merge sort algorithm

Now for merging function, for merging function we will have two copies, one as Fast-Run and another for Details to print-out the running Steps, this will make the Fast-Run Function short and easy to follow-up. So, here is the Fast-Run Function code for merge the two part of array returned from the merge_sort_divider. Here is the Code ..

Run time screen ..

End of Merge Sorting Algorithm.

To Download my Python code (.py) files Click-Here

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By: Ali Radwani

Categories: Learning, Lesson, math, Problem, Projects/Experiments, Python Tags: ahradwani.com, Algorithm, Ali, Code, Learning, merge sort, Project, Python, radwani

Python: Sorting Algoritm – Bubble Sort

June 1, 2021 Ali Radwani 3 comments

Learning : Python, Math, Algorithm
Subject: Sorting Algoritm – Bubble Sort

[NOTE: To keep the code as simple as we can, We WILL NOT ADD any user input Varevecations. Assuming that our user will Enter the right inputs.]

Sorting Algorithm is a way to sort a given list of numbers, there are several sorting Algorithm as follow:
Type of Sorting Algorithm
Quick Sort. [Click to Read]
Bubble Sort.
Merge Sort. [Commeing Soon]
Insertion Sort. [Commeing Soon]
Selection Sort. [Commeing Soon]
Heap Sort. [Commeing Soon]
Radix Sort. [Commeing Soon]
Bucket Sort. [Commeing Soon]

Bubble Sort: Steps of Bubble Sorting Algorithm are:
1. We will select the First Number (Current number) in the list and Compare it with the next number in the list. (Compare list[0] and list[1])

2. If the Next Number in the list IS SMALLER than Current Number SWAP the Two, then compare the Current with the third number and so on.

2.2 If the Next Number in the list IS NOT SMALLER than Current Number, Then we LEFT the Current Number in it’s Position and will Set the Next number as the Current. And will start Comparing Again as Step 2 until the last number in the list.

3. When we reach the end of the list and we perform a SWAP, then we start again with First Element as STEP 1.

4. If we reach the end of the list Without any SWAP being made, then the list is ordered and the algorithm can stop.

Coding Starting with the Main Menu Function and a Function to ask the
User to enter the numbers in the list, here are those two Functions.

python code bubble sorting algorithm project by Ali Radwani doha qatar

And here is the Main code that will call the Menu and trigger the Functions based on the User selecting.

Also we have the Function that will ask the user to Enter the Numbers for the List or Array to be sort.
All the code will be Available as a .py file in the Download Page [Click Here]

Now let’s see the code for Bubble Sorting Algorithm, we will have two version of the code, one for Fast-Run that takes the list and return it back as Sorted, and another one will be to show the Details Step By Step of applying the Algorithm. Both Functions are the same but the details one will have several print statements to show the steps, here I am posting the Fast-Run version.