Project 1: The Matrix and Plotting Playground

Build a sandbox that creates matrices and visualizes them as plots and images.

Project Overview

Attribute Value
Difficulty Level 1: Beginner
Time Estimate Weekend
Main Language MATLAB
Alternative Languages Python (NumPy), Octave
Knowledge Area Matrices and plotting
Tools MATLAB plotting tools
Main Book “MATLAB: An Introduction with Applications” by Amos Gilat

What you’ll build: A script that generates matrices, visualizes them, and plots related functions.

Why it teaches MATLAB: MATLAB is built around matrix operations and visualization. This project makes both second nature.

Core challenges you’ll face:

  • Building matrices programmatically
  • Understanding indexing and slicing
  • Choosing appropriate plot types

Real World Outcome

You will produce plots and heatmaps showing matrix patterns (identity, random, gradients) and function curves.

Example Output:

>> matrix_playground
Generated matrices: identity, random, gradient
Saved plots: sine.png, heatmap.png

Verification steps:

  • Confirm matrix shapes and values
  • Verify plots match expected patterns

The Core Question You’re Answering

“How do I manipulate matrices and instantly visualize results in MATLAB?”

This is the core MATLAB workflow.

Concepts You Must Understand First

Stop and research these before coding:

  1. Matrix creation
    • How do you build identity, zeros, and random matrices?
    • Book Reference: “MATLAB: An Introduction with Applications” by Amos Gilat, Ch. 2
  2. Indexing and slicing
    • How do you extract rows, columns, and submatrices?
    • Book Reference: “MATLAB: An Introduction with Applications” by Amos Gilat, Ch. 2
  3. Plot types
    • When do you use line plots vs imagesc or mesh?
    • Book Reference: “MATLAB: An Introduction with Applications” by Amos Gilat, Ch. 4

Questions to Guide Your Design

  1. Visualization choices
    • Which matrix patterns are best shown as heatmaps?
    • How will you label axes and titles consistently?
  2. Script organization
    • Will you keep each experiment in separate functions?
    • How will you save outputs automatically?

Thinking Exercise

Matrix Pattern

Create a 5x5 matrix where each element is the sum of its row and column index. Predict the heatmap pattern.

Questions while working:

  • What symmetry appears?
  • How does scaling affect the color map?

The Interview Questions They’ll Ask

Prepare to answer these:

  1. “Why is MATLAB matrix-first?”
  2. “How does indexing work in MATLAB?”
  3. “When do you use imagesc vs plot?”
  4. “How do you save plots programmatically?”
  5. “What is vectorization and why is it faster?”

Hints in Layers

Hint 1: Starting Point Start with identity and random matrices.

Hint 2: Next Level Use meshgrid to build gradient patterns.

Hint 3: Technical Details Experiment with colormaps to highlight structure.

Hint 4: Tools/Debugging Display matrix values alongside plots for sanity checks.

Books That Will Help

Topic Book Chapter
Matrix basics “MATLAB: An Introduction with Applications” by Amos Gilat Ch. 2
Indexing “MATLAB: An Introduction with Applications” by Amos Gilat Ch. 2
Plotting “MATLAB: An Introduction with Applications” by Amos Gilat Ch. 4

Implementation Hints

  • Use vectorized operations instead of loops.
  • Save figures automatically with consistent naming.
  • Build a small menu to run different demos.

Learning Milestones

  1. First milestone: You can create and manipulate matrices.
  2. Second milestone: You can visualize matrices with multiple plot types.
  3. Final milestone: You can explain when each plot type is appropriate.