Lesson 1.3 · 3 of 25 lessons

Matrix columns

Connect row and column pictures of a system to elimination, LU, and inverse matrices.

Open the interactive animation

01 · Story

What to verify in this scene

Follow the explanations and operations, then identify the mathematical evidence that remains in the final scene.

  1. 01

    Columns c1 and c2 of A are the destinations of basis vectors i and j

  2. 02

    Hide the column arrows, then apply A to send the basis and grid to those destinations

  3. 03

    i reached the first column and j reached the second
    A matrix lists the new destinations of the basis

02 · Notebook

The runnable notebook

This source creates the mathematical objects and controls the order of operations and animation. Read it here, then play the same scene yourself.

2d
zoom 9/10
grid on
relative-grid off
basis off
coordinates on

1 1  #A
0 1

col(A, 1)  #c1@
col(A, 2)  #c2@
// Columns {{c1}} and {{c2}} of {{A}} are the destinations of basis vectors {{i}} and {{j}}
focus c1 c2
checkpoint Matrix columns

clear
basis on
relative-grid on
// Hide the column arrows, then apply {{A}} to send the basis and grid to those destinations
A
// {{i}} reached the first column and {{j}} reached the second\nA matrix **lists the new destinations of the basis**
Open the interactive animation

03 · Unit 1

Lessons in this unit

Matrices & Gaussian elimination — Connect row and column pictures of a system to elimination, LU, and inverse matrices.

  1. 1.1Two views of a system
  2. 1.2Gaussian elimination
  3. 1.3Matrix columns
  4. 1.4LU factorization
  5. 1.5Inverse matrices