% Matlab diary from cs111, Oct 3 2007.
%
% This is what I typed in class.  
%
% Type it into Matlab yourself to
% reproduce the output I showed.

diary on
finitefern(10000)
finitefern(100000)
edit fern
A1 = [ .85  .04; -.04  .85];  b1 = [0; 1.6];
A1
b1
x = [.5 ; .5]
I
eye(2)
eye(7)
I =eye(2)
I-A1
A1
A = I - A1
d =[ 2 ;3 ]
A
d * A
d = d'
d =
     2     3
A
d * A
x = A \ b1
A * x 
b1
residual = b1 - A*x
axis on
axis( [ -3 5 0 12])
hold on
x1 = -3 : 5
x2 = .15*x1 / .04
plot(x1, x2)
x2 = (-.04*x1 + 1.6) /.15
plot(x1,x2,'r')

clc
clear
load temperature
whos
A4
b4
clc
spy(A4)
t = A4\b4
T = reshape(t,4,4)
T = T'
T = flipud(T)

size(A100)
spy(A100),shg
size(b100)
b100(1)
b100(100)
b100(101)
t = A100 \ b100;
t
T = reshape(t,100,100);
T
T = flipud(T');
max(t)
min(t)
size(T)
surf(T)
help surf
help surfc
surfc(T)
diary off