2-Dimensional Matrix

Let empty = 0, brown = 1, white = 2, blue = 3

2-d Matrices in Matlab

K = zeros(2,6)
L = 2*ones(2,6)
N = zeros(5,6) N(2:3,2:3) = 1
S = randi(2,3,6)
T = randi(3,3,6)

3-Dimensional Matrix

3 x 3 x 3
4 x 4 x 4
1000 x 1000 x 1000 rho, theta, phi

3-d Matrices in Matlab

B = randi(6,3,3,3)
C = randi(6,4,4,4)

4-Dimensional Matrix

Tesseract

Time and Space

N-Dimensional Matrix

Intermission

Simple Math

A * B

B * A

Simple Math

Ax = b

Simple Math

Ax = b in Matlab

A = [1 -2 3 ; 2 1 1 ; -3 2 -2]; b = [7 ; 4 ; -10]; tic x1 = inv(A)*b toc tic x2 = A\b toc

A = randi(100,1000,1000); b = randi(50,1000,1); tic x1 = inv(A)*b; toc tic x2 = A\b; toc

A = rand(10000); b = rand(10000,1); tic x1 = inv(A)*b; toc tic x2 = A\b; toc

Examples

Algorism and Bushism of the Day

"One of the hardest parts of my job is to connect Iraq to the war on terror."	"There's an old African proverb that says 'If you want to go quickly, go alone. If you want to go far, go together.' We have to go far — quickly."

Lesson of the Day

Failure – a few errors in judgment practiced everyday
in 30 days things are getting worse – imagine what happens in 5 years

Success – a few new disciplines practiced everyday
in 30 days things are getting better – imagine what happens in 5 years

Fix the errors of the past and pick up a few new disciplines for the future

It is impossible for a man to learn what he thinks he already knows.

Word of the day

LL

The End