UNIVERSITY OF WEST ATTICA
SCHOOL OF ENGINEERING
DEPARTMENT OF COMPUTER ENGINEERING AND INFORMATICS

University of West Attica · Department of Computer Engineering and Informatics

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Signals and Systems

Learning of Matlab

Vasileios Evangelos Athanasiou
Student ID: 19390005

GitHub · LinkedIn

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Supervision

Supervisor: Adonis Bogris, Professor

UNIWA Profile · LinkedIn

Co-supervisor: Georgios Antoniou, Laboratory Teaching Staff

UNIWA Profile

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Athens, April 2021

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README

Learning of Matlab

This README provides an overview of the MATLAB laboratory assignment completed for the Signals and Systems course.

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Table of Contents

Section	Folder/File	Description
1	assign/	Assignment instructions and exercise description
1.1	assign/EXERCISE 1 - LEARNING OF MATLAB.pdf	Exercise instructions (English)
1.2	assign/ΑΣΚΗΣΗ 1 - ΕΚΜΑΘΗΣΗ ΤΟΥ MATLAB.pdf	Exercise instructions (Greek)
2	docs/	Documentation related to MATLAB learning exercises
2.1	docs/Learning-of-Matlab.pdf	MATLAB learning documentation (English)
2.2	docs/Εκμάθηση-του-Matlab.pdf	MATLAB learning documentation (Greek)
3	src/	MATLAB source code files
3.1	src/m.m	MATLAB script file
3.2	src/m1.m	MATLAB script file
3.3	src/m2.m	MATLAB script file
3.4	src/m3.m	MATLAB script file
3.5	src/m4.m	MATLAB script file
3.6	src/m5.m	MATLAB script file
4	README.md	Project documentation
5	INSTALL.md	Usage instructions

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1. Project Overview

This assignment covers fundamental MATLAB operations, including:

• Vector manipulation
• Custom function creation
• Complex number analysis
• Mathematical visualization and plotting

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2. Exercise Summaries

2.1 Vector Operations

Objective: Create and manipulate vectors a and b.

Key Operations:

• Vector a defined in interval [0, 10] with step 0.1.
• Vector b defined as cos(x) for interval [0, 20] with step 0.2.
• Computations included:
  • Division (a / b)
  • Element-wise power (a.^4)
  • Inner product (a · b')

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3. Unit Conversion Function

Objective: Convert radians to degrees.

• Function name: gwnia(rad)
• Logic: Multiplies input by 180/π
• Verification:
  π/4 radians correctly converted to 45 degrees.

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4. Sinc Function Visualization

Objective: Plot the sinc function.

Function definition: sinc(x) = sin(πx) / (πx)

Implementation:

• Interval defined from -2 to 2.
• Plot formatted using:
  • plot
  • title
  • xlabel
  • ylabel

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5. Complex Number Analysis

Objective: Extract properties of a complex number.

• Function name: praxis(z)
• Outputs:
  • Phase (angle)
  • Magnitude (absolute value)
  • Real part
  • Imaginary part

Test cases included:

• i
• -i
• 1
• e^(3 + 4i)

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6. Multi-Plotting & Subplots

Objective: Compare two mathematical functions:

$$ f(x) = x e^{-x} $$

$$ y(x) = 2 \cos(x) $$

Features:

• Figure 1: Both functions plotted together with legend.
• Figure 2: Functions displayed in separate vertical subplots for clearer comparison.

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7. Technical Commands Used

Command	Description
linspace	Generates linearly spaced vectors
subplot	Creates multiple plots in one figure
angle, abs	Compute phase and magnitude of complex numbers
real, imag	Extract real and imaginary parts

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8. Summary

The laboratory assignment demonstrates proficiency in MATLAB basics, function creation, complex number manipulation, and data visualization techniques used in signals and systems analysis.