🧠 Learning Journal – Python & Computer Science | Day 1


Arrays, Lists… and Jagged What!?
Today I dove into one of the most basic yet deep concepts in programming: arrays.
At first glance, arrays might seem like a beginner's topic, just a list of items, right?
But the more I explored, the more I realized… there's a whole ecosystem of array types, especially in Python, and each has a specific use case.
🔍 What I learned
✅ Python Lists
In Python, lists
are super flexible:
They can grow and shrink dynamically.
They can store different data types.
They're great for everyday programming.
✅ NumPy Arrays
For serious number crunching, you’ll want to use NumPy arrays:
Fixed type (all elements must be the same type)
Faster and more memory-efficient
Optimized for math, data analysis, machine learning
✅ Multidimensional & Jagged Arrays
This is where things got interesting.
2D arrays: Think of spreadsheets or matrices.
3D arrays: Layers of 2D arrays… great for image processing or tensor operations.
Jagged arrays: Arrays where each "row" can have a different length.
Example? Storing student grades where each student took a different number of exams.notes = [[90, 85], [100, 92, 88], [70]]
🤯 Key Takeaways
Arrays are not all equal — use the right type for the right task.
Multidimensional arrays open the door to real-world data (images, tables, nested structures).
Jagged arrays are powerful when data is irregular.
🔄 Coming up next
➡️ Linked Lists : those weird pointer chains that haunt CS students 😅
But I’m excited to break them down and understand their purpose.
✍️ Why I'm doing this
I’m learning in public to reinforce my understanding and connect with others on the same path, toward data science, machine learning, or just becoming a better programmer.
If you’ve got any cool tricks or real-life use cases for arrays, I’m all ears 👂
Thanks for reading!
📅 See you in Day 2.
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