Lecture 0 - Get an Editable Window for a Figure in Python | Linear Algebra I

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Lecture 0 - Get an Editable Window for a Figure in Python public

Lecture 1 - Introduction to Linear Algebra I public

Lecture 2 - Solution of Some Systems public

Lecture 3 - The Matrix View

Lecture 4 - Solve a Square Matrix Equation in Python public

Lecture 5 - Application to Astronomy public

Lecture 6 - Discover the Systems of Linear Equations public

Linear Algebra I - Section 2 Test public

Lecture 7 - Discover the Row Echelon form

Lecture 8 - Back Substitution in Python for Regular Systems in Row Echelon Form

Lecture 9 - Gaussian Elimination and Back Substitution

Lecture 10 - Gaussian Elimination and Back Substitution in Python

Lecture 11 - Gauss Jordan Elimination

Lecture 12 -Gauss Jordan Elimination in Python

Lecture 13 - Around the Row Echelon Form of a System

Linear Algebra I - Section 3 Test

Lecture 14 - Examples of Pivot

Lecture 15 - Gaussian Elimination with Pivoting

Lecture 16 - Gaussian Elimination with Pivoting in Python

Lecture 17 - Gauss Jordan Elimination with Pivoting in Python

Lecture 18 - Pivoting for Gaussian and Gauss Jordan Elimination

Linear Algebra I - Section 4 Test

Lecture 19 - Examples of Singular System with an Infinity of Solutions

Lecture 20 - Examples of Singular System with no Solution

Lecture 21 - Analyse Singular Systems with Gaussian Elimination with Pivoting

Lecture 22 - Solve singular systems with Gauss Jordan Elimination with Pivoting

Lecture 23 - The Case of Singular Matrices

Linear Algebra I - Section 5 Test

Lecture 24 - Examples of Underdetermined Systems

Lecture 25 - Analyse Underdetermined Systems with Gaussian Elimination with Pivoting

Lecture 26 - Solve Underdetermined Systems with Gauss Jordan Elimination with Pivoting

Lecture 27 - Examples of Overdetermined Systems

Lecture 28 - Least Square Optimization in Python

Lecture 29 - The Case of Rectangular Matrices

Linear Algebra I - Section 6 Test

Lecture 30 - About Homogeneous Systems

Lecture 31 - Gauss Jordan Elimination for a Square Homogeneous System

Lecture 32 - Gauss Jordan Elimination for an Underdetermined Homogeneous System

Lecture 33 - Gauss Jordan Elimination for an Overdetermined Homogeneous System

Lecture 34 - The Homogeneous Systems

Linear Algebra I - Section 7 Test

Lecture 35 - Discover Matrices and Vectors in Python

Lecture 36 - Definition of Matrices, Line Vectors and Column Vectors

Lecture 37 - Particular Matrices

Lecture 38 - Diagonal Matrices

First published on Saturday, Aug 22, 2026 and last modified on Tuesday, Sep 1, 2026

Lecture 0 - Get an Editable Window for a Figure in Python

Fabienne Chaplais Email

from numpy import *
from matplotlib.pyplot import *

#definition of functions
x=arange(-10,11,0.1)
y0=0*x
y1=x
y2=-x
y3=(2/3)*x-(4/5)
y4=-(2/3)*x+(4/5)

#Draw Straight Lines
plot(x,y0,label='y=0')
plot(x,y1,label='y=x')
plot(x,y2,label='y=-x')
plot(x,y3,label='y=(2/3)*x-(4/5)')
plot(x,y4,label='y=-(2/3)*x+(4/5)')
plot(y0,x,label='x=0')
legend()

xlim(-15,15)
ylim(-15,15)
grid()
title('Straight Lines')

1 Section 1 - Preliminaries

2 Section 2 - Discover the Systems of Linear Equations

3 Section 3 - Around the Row Echelon Form of a System

4 Section 4 - Pivoting for Gaussian and Gauss Jordan Elimination

5 Section 5 - The Case of Singular Matrices

6 Section 6 - The Case of Rectangular Matrices

7 Section 7 - The Homogeneous Systems

8 Section 8 - Matrices, Line Vectors and Column Vectors