%%% matrices.m: to run this script noninteractively, type
%%% matlab < matrices.m > matrices.out
%%%
%%% will dump output into file matrices.out
%%%
%%% contains some examples of array and matrix manipulation

clc
echo on

%% To create a vector
v = [1.0 2 3.0 4.0]

%% To create a a 2x4 matrix
A = [4.0 5.0 7.0 8.0;  9.0 10.0 11.0 12.0]

%% To create a main diagonal matrix
D = diag(v)

%% Add an above main diagonal
D = D + diag([pi  pi pi], 1)

%% Add a below main diagonal, now D is tridiagonal
D = D + diag([-1 -2 -2], -1)

%% Combine the blocks D and the 4x4 identity into an 8x4 matrix
%% notice the answer is left in the special variable ans
[D; eye(4)]

%% a 3x3 matrix of all zeros (done 2 different ways)
Z = zeros(3)
Z = zeros(3,3)

%% a matrix of all ones
O = ones(2,3)