Forem: Onaolapo-11

The Sieve of Eratosthenes obtains the primes in a given range by eliminating the multiples of primes beginning from 2

Onaolapo-11 — Fri, 10 Apr 2026 21:57:56 +0000

[Reset] Day 6 [April 10th, 2026]

Goals:
"Day 3-4: Control structures (if-else, loops)" (Meta AI, personal communication, August 8, 2025)

Notes:
Python for Software Development' textbook by Halvorsen (n.d.):

To solve, the current task: "Create a Python Script where you find all prime numbers between 1 and 200", I learnt that an efficient method that can be used is the Sieve of Eratosthenes (Geeksforgeeks, 2025; Loucka, 2023).
The Sieve of Eratosthenes obtains the primes in a given range by eliminating the multiples of primes beginning from 2 (Geeksforgeeks, 2025; Loucka, 2023). AS you progress, you will discover some multiples are eliminated.

SIEVE OF ERATOSTENES ALGORITHM (Geeksforgeeks, 2025) [With my additional notes]:

def sieve(num): #num is the extent for which we want to check for primes

#we have to monitor if the numbers are prime

prime = [True] * (num + 1)   #we have + 1 because the number in focus has to be captured

p = 2     #2 is the lowest prime number

  
  
  Sieve of Erastostenes algorithm


while p * p <= num: #the product of the prime less than or equal to num. Why? The Sieve of Eratosthenes obtains the primes in a given range by eliminating the multiples of primes beginning from 2.

    if prime[p]: #from the prime list at index p #showing us p = True at that particular prime

    #Mark all multiples of p as non-prime
    for i in range (p * p, num + 1, p):   #this range starts from the square of p and increases as multiples in p steps
        prime[i] = False
p += 1




  
  
  creating the list of all prime numbers


res = []

for p in range(2, n + 1):

    if prime[p]:

        res.append(p)

return res

Evaluating the code below outputs the prime numbers between 1 and 200:

if name == "main":
n = 200
res = sieve(n)
for ele in res:
print(ele, end=' ')

Output:

2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97 101 103 107 109 113 127 131 137 139 149 151 157 163 167 173 179 181 191 193 197 199

Summary:
The Sieve of Eratosthenes obtains the primes in a given range by eliminating the multiples of primes beginning from 2.

References:

Geeksforgeeks. (2025, July 23). Sieve of Eratosthenes. https://www.geeksforgeeks.org/dsa/sieve-of-eratosthenes/
Loucka, T. (2023, October 30). What are prime numbers? Doodlelearning. https://doodlelearning.com/maths/skills/numbers/prime-number-guide
Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4

Sieve of Eratosthenes: An efficient method to find a set of prime numbers up to a certain point.

Onaolapo-11 — Sun, 22 Mar 2026 23:29:00 +0000

[Reset] Day 5 [March 22nd, 2026]

Goals:
"Day 3-4: Control structures (if-else, loops)" (Meta AI, personal communication, August 8, 2025)

Notes:
Python for Software Development' textbook by Halvorsen (n.d.):

To solve, the current task: "Create a Python Script where you find all prime numbers between 1 and 200", I learnt that an efficient method that can be used is the Sieve of Eratosthenes (Geeksforgeeks, 2025; Loucka, 2023). I will study this better in my next session.

Summary:
I learnt that an efficient method that can be used to find a set of prime numbers up to a certain point is the Sieve of Eratosthenes.

References:

Geeksforgeeks. (2025, July 23). Sieve of Eratosthenes. https://www.geeksforgeeks.org/dsa/sieve-of-eratosthenes/
Loucka, T. (2023, October 30). What are prime numbers? Doodlelearning. https://doodlelearning.com/maths/skills/numbers/prime-number-guide
Halvorsen, H. (n.d.)._ Python_. https://halvorsen.blog/documents/programming/python/python.php#python4

I looked at the Fibonacci sequence

Onaolapo-11 — Sat, 21 Mar 2026 21:07:16 +0000

[Reset] Day 4 [March 21st, 2026]

Goals:
"Day 3-4: Control structures (if-else, loops)" (Meta AI, personal communication, August 8, 2025)

Notes:
Python for Software Development' textbook by Halvorsen (n.d.):

I looked at the Fibonacci sequence and nesting for loops.
Current task to solve: "Create a Python Script where you find all prime numbers between 1 and 200."

Summary:
I looked at the Fibonacci sequence

References:

Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4

Arrays in Python differ from Lists and Tuples

Onaolapo-11 — Fri, 20 Mar 2026 22:05:17 +0000

[Reset] Day 3 [March 20th, 2026]

Unfortunately didn't keep to my original goals, but here's a reset. Based on the Meta AI structured plan for 12-weeks (Meta AI, personal communication, August 8, 2025), I am on Day 3. Hence, final date for the goal is June 11th, 2026. If I move fast, I can beat it.

Goals:
"Day 3-4: Control structures (if-else, loops)" (Meta AI, personal communication, August 8, 2025)

Notes:
Python for Software Development' textbook by Halvorsen (n.d.):
In previous tutorials, I have learnt about if-else statements, as well as about for and while loops.

Arrays can store multiple values at the same time.
Arrays in Python differ from Lists and Tuples (Geeksforgeeks, 2025)

Summary:
Arrays in Python differ from Lists and Tuples

References:

Geeksforgeeks. (2025, July 15). Python list vs array vs tuple. https://www.geeksforgeeks.org/python/python-list-vs-array-vs-tuple/
Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4

Why integer objects in python are not iterable

Onaolapo-11 — Fri, 16 Jan 2026 22:39:46 +0000

Day 81 [January 16th, 2025]

I need to buckle down, as I'm still lagging on day day 3 & 4 goals, "Day 3-4: Control structures (if-else, loops)", as well as day 5 (and 6) goals, "Day 5-6: Functions and modules", and Day 7 target (exercises) (Meta AI, personal communication, August 8, 2025). If I haven't covered this, I can't make progress on day 8 - 80 goals.

Goals:
As extracted from the 'Python for Software Development' textbook by Halvorsen (n.d.):

Plotting in Python ✅
Subplots✅
Exercises✅
If ... Else
Arrays
For Loops
Nested
For Loops
While Loops
Exercises
Creating Functions in Python - Introduction
Functions with multiple return values
Exercises
Creating Classes in Python
The init () Function
Exercises
Creating Python Modules
Exercises

Notes:
Python for Data Science, AI & Development Course (IBM) (Santarcangelo, n.d.):
Module 3: Python Programming Fundamentals

While doing the Hands-on-Lab for the topic on Loops (Santarcangelo, n.d.),

After inputting this code:
dates = [1997,2001,20003]
N = len(dates)

for i in N:
print(dates[1])

I got a TypeError:

TypeError Traceback (most recent call last)
Cell In[8], line 4
1 dates = [1997,2001,20003]
2 N = len(dates)
----> 4 for i in N:
5 print(dates[1])

TypeError: 'int' object is not iterable

So a question came to mind: 'Why are integer objects in python not iterable?'
I found this:

Why integer objects in python are not iterable (Ramakrishna, 2021):

Contain singular integer values
Do not have 'iter' method

print(dir(int)) shows if an object contains 'iter' method or not (Ramakrishna, 2021).

Summary:
I learnt why integer objects in python are not iterable.

References:

Ramakrishna, S. (2021, September 9). How to fix the python typerror: ‘int’ object is not Iterable. Hackernoon. https://hackernoon.com/how-to-fix-the-python-typeerror-int-object-is-not-tterable
Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4
Santarcangelo, J. (n.d.). Python for data science, AI & development [MOOC]. Coursera. https://coursera.org/learn/python-for-applied-data-science-ai

enumerate() function is used as a counter in python when iterating data

Onaolapo-11 — Sun, 11 Jan 2026 17:52:35 +0000

Day 80 [January 11th, 2025]

Goals:
As extracted from the 'Python for Software Development' textbook by Halvorsen (n.d.):

Plotting in Python ✅
Subplots✅
Exercises✅
If ... Else
Arrays
For Loops
Nested
For Loops
While Loops
Exercises
Creating Functions in Python - Introduction
Functions with multiple return values
Exercises
Creating Classes in Python
The init () Function
Exercises
Creating Python Modules
Exercises

Notes:
Python for Data Science, AI & Development Course (IBM) (Santarcangelo, n.d.):
Module 3: Python Programming Fundamentals

enumerate() function is used as a counter in python when iterating data, enabling to monitor the item and its position in the list (Geeksforgeeks, 2025; Santarcangelo, n.d.; Meta AI, personal communication, January 11, 2025).

Summary:
enumerate() function is used as a counter in python when iterating data

References:

Geeksforgeeks. (2025, September 12). Enumerate() in python.
https://www.geeksforgeeks.org/python/enumerate-in-python/
Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4
Santarcangelo, J. (n.d.). Python for data science, AI & development [MOOC]. Coursera. https://coursera.org/learn/python-for-applied-data-science-ai

I completed the section on Conditions and Branching

Onaolapo-11 — Mon, 08 Dec 2025 22:59:05 +0000

Day 79 [December 8th, 2025]

Goals:
As extracted from the 'Python for Software Development' textbook by Halvorsen (n.d.):

Plotting in Python ✅
Subplots✅
Exercises✅
If ... Else
Arrays
For Loops
Nested
For Loops
While Loops
Exercises
Creating Functions in Python - Introduction
Functions with multiple return values
Exercises
Creating Classes in Python
The init () Function
Exercises
Creating Python Modules
Exercises

Notes:
Python for Data Science, AI & Development Course (IBM) (Santarcangelo, n.d.):
Module 3: Python Programming Fundamentals

Conditions and Branching

The block of code under if statement only run when the if condition is True
Comparison of strings is lexicographically-sensitive (comparison is done on a character by character basis dependent on how the characters are ordered in Unicode or ASCII) (see also Google, 2025a; Google, 2025b). That's why "10"<"7" evaluates to True (the first characters are compared).

Summary:
I completed the section on Conditions and Branching.

References:

Google. (2025a). Google Search with AI. [Large language model]. https://www.google.com/search?q=in+python+is+%2210%22+less+than+%227%22%3F&oq=in+python+is+%2210%22+less+than+%227%22%3F&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIHCAEQIRigATIHCAIQIRigATIHCAMQIRigATIHCAQQIRigATIHCAUQIRiPAjIHCAYQIRiPAjIHCAcQIRiPAtIBCTEyMzYwajBqOagCBrACAfEFn-fcgSi5fxs&sourceid=chrome&ie=UTF-8
Google. (2025b). Google Search with AI. [Large language model]. https://www.google.com/search?q=Comparison+of+strings+is+lexicographically-sensitive&oq=Comparison+of+strings+is+lexicographically-sensitive&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIKCAEQABiABBiiBDIHCAIQABjvBTIKCAMQABiABBiiBNIBBzQ3NmowajmoAgawAgHxBWWZfDjzK9C2&sourceid=chrome&ie=UTF-8
Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4
Santarcangelo, J. (n.d.). P_ython for data science, AI & development_ [MOOC]. Coursera. https://coursera.org/learn/python-for-applied-data-science-ai

Comparison of strings is lexicographically-sensitive

Onaolapo-11 — Tue, 02 Dec 2025 00:03:24 +0000

Day 78 [December 2nd, 2025 started reading around 12am]

Goals:
As extracted from the 'Python for Software Development' textbook by Halvorsen (n.d.):

Plotting in Python ✅
Subplots✅
Exercises✅
If ... Else
Arrays
For Loops
Nested
For Loops
While Loops
Exercises
Creating Functions in Python - Introduction
Functions with multiple return values
Exercises
Creating Classes in Python
The init () Function
Exercises
Creating Python Modules
Exercises

Notes:
Python for Data Science, AI & Development Course (IBM) (Santarcangelo, n.d.):
Module 3: Python Programming Fundamentals

Conditions and Branching

The block of code under if statement only run when the if condition is True
Comparison of strings is lexicographically-sensitive (comparison is done on a character by character basis dependent on how the characters are ordered in Unicode or ASCII) (see also Google, 2025a; Google, 2025b). That's why "10"<"7" evaluates to True (the first characters are compared).

Summary:
Comparison of strings is lexicographically-sensitive.

References:

Google. (2025a). Google Search with AI. [Large language model]. https://www.google.com/search?q=in+python+is+%2210%22+less+than+%227%22%3F&oq=in+python+is+%2210%22+less+than+%227%22%3F&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIHCAEQIRigATIHCAIQIRigATIHCAMQIRigATIHCAQQIRigATIHCAUQIRiPAjIHCAYQIRiPAjIHCAcQIRiPAtIBCTEyMzYwajBqOagCBrACAfEFn-fcgSi5fxs&sourceid=chrome&ie=UTF-8
Google. (2025b). Google Search with AI. [Large language model]. https://www.google.com/search?q=Comparison+of+strings+is+lexicographically-sensitive&oq=Comparison+of+strings+is+lexicographically-sensitive&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIKCAEQABiABBiiBDIHCAIQABjvBTIKCAMQABiABBiiBNIBBzQ3NmowajmoAgawAgHxBWWZfDjzK9C2&sourceid=chrome&ie=UTF-8
Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4
Santarcangelo, J. (n.d.). Python for data science, AI & development [MOOC]. Coursera. https://coursera.org/learn/python-for-applied-data-science-ai

Comparison of strings is case-sensitive

Onaolapo-11 — Sat, 29 Nov 2025 19:03:58 +0000

Day 77 [November 29, 2025]

Goals:
As extracted from the 'Python for Software Development' textbook by Halvorsen (n.d.):

Plotting in Python ✅
Subplots✅
Exercises✅
If ... Else
Arrays
For Loops
Nested
For Loops
While Loops
Exercises
Creating Functions in Python - Introduction
Functions with multiple return values
Exercises
Creating Classes in Python
The init () Function
Exercises
Creating Python Modules
Exercises

Notes:
Python for Data Science, AI & Development Course (IBM) (Santarcangelo, n.d.):
Module 3: Python Programming Fundamentals

Conditions and Branching

if, else and elif statements
Comparison operators: == equal to, != not equal to, < less than, > greater than
Logic operators: or, and
"or" outputs False, only when both operands are False
"and" outputs True, only when both operands are True
Comparison of strings is case-sensitive, e.g. "boy" == "BOY" outputs False, meaning they're not equal to each other.
Likewise in accordance to the value of letters by ASCII, symbols/words/letters, can be compared to one another, e.g. according to ASCII's order of character, "a" is at position 97, while "A" is at position 65, meaning that the code "a" > "A" will output True, while "A" > "a" will output False

Summary:
Comparison of strings is case-sensitive.

References:

Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4
Santarcangelo, J. (n.d.). Python for data science, AI & development [MOOC]. Coursera. https://coursera.org/learn/python-for-applied-data-science-ai

I completed Module 2 (Python Data Structures) of Python for Data Science, AI & Development Course (IBM) (Santarcangelo, n.d.)

Onaolapo-11 — Mon, 24 Nov 2025 20:01:45 +0000

Day 76 [November 24, 2025]

Goals:
As extracted from the 'Python for Software Development' textbook by Halvorsen (n.d.):

Plotting in Python ✅
Subplots✅
Exercises✅
If ... Else
Arrays
For Loops
Nested
For Loops
While Loops
Exercises
Creating Functions in Python - Introduction
Functions with multiple return values
Exercises
Creating Classes in Python
The init () Function
Exercises
Creating Python Modules
Exercises

Notes:
Python for Data Science, AI & Development Course (IBM) (Santarcangelo, n.d.):
Module 2: Python Data Structures

Lists and Tuples
Dictionaries
Sets

Sets:

used for the storage of values that are distinct
"append() adds an object as a single element, while extend() adds each element of an iterable individually". Check using the code below:

list = [2,3,4]
list.append([3])
print(list)

list2 = [2,3,4]
list2.extend([3]) #note the difference here
print(list2)

Outputs:
[2, 3, 4, [3]]
[2, 3, 4, 3]

Otherwise,
list2 = [2,3,4]
list2.extend(3) #note the difference here
print(list2)
will give TypeError: 'int' object is not iterable

Both sum() and len() functions work for Tuples, but the difference is sum() adds the elements (must be int or float type), while len() counts the elements.

ages = (20,3,34)
print(sum(ages))
print(len(ages))

Outputs:
57
3

Summary:
I completed Module 2 (Python Data Structures) of Python for Data Science, AI & Development Course (IBM) (Santarcangelo, n.d.).

References:

Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4
Santarcangelo, J. (n.d.). Python for data science, AI & development [MOOC]. Coursera. https://coursera.org/learn/python-for-applied-data-science-ai

Sets do not possess order

Onaolapo-11 — Fri, 21 Nov 2025 22:10:39 +0000

Day 75 [November 21, 2025]

Goals:
As extracted from the 'Python for Software Development' textbook by Halvorsen (n.d.):

Plotting in Python ✅
Subplots✅
Exercises✅
If ... Else
Arrays
For Loops
Nested
For Loops
While Loops
Exercises
Creating Functions in Python - Introduction
Functions with multiple return values
Exercises
Creating Classes in Python
The init () Function
Exercises
Creating Python Modules
Exercises

Notes:
Python for Data Science, AI & Development Course (IBM) (Santarcangelo, n.d.):
Module 2: Python Data Structures

Lists and Tuples
Dictionaries
Sets

Sets:

sets do not possess order. Dictionaries
.items() method is used to extract all key-value pairs as tuples, all itemized in a list: listOfItems = list(nameOfDict.items())

Summary:
Sets do not possess order.

References:

Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4
Santarcangelo, J. (n.d.). Python for data science, AI & development [MOOC]. Coursera. https://coursera.org/learn/python-for-applied-data-science-ai

The difference method shows us the elements of one set that are not found in the other

Onaolapo-11 — Thu, 20 Nov 2025 22:02:57 +0000

Day 74 [November 20, 2025]

Goals:
As extracted from the 'Python for Software Development' textbook by Halvorsen (n.d.):

Plotting in Python ✅
Subplots✅
Exercises✅
If ... Else
Arrays
For Loops
Nested
For Loops
While Loops
Exercises
Creating Functions in Python - Introduction
Functions with multiple return values
Exercises
Creating Classes in Python
The init () Function
Exercises
Creating Python Modules
Exercises

Notes:
Python for Data Science, AI & Development Course (IBM) (Santarcangelo, n.d.):
Module 2: Python Data Structures

Lists and Tuples
Dictionaries
Sets

Sets:

.difference method shows us the elements of one set (e.g. setBIg) that are not found in the other(setCar): setBig.difference(setCar) [note the arrangement of the set, because reversing the arrangement of the set, is different from the other).

Summary:
The difference method shows us the elements of one set that are not found in the other.

References:

Halvorsen, H. (n.d.). Python. https://halvorsen.blog/documents/programming/python/python.php#python4
Santarcangelo, J. (n.d.). Python for data science, AI & development [MOOC]. Coursera. https://coursera.org/learn/python-for-applied-data-science-ai