A=[1 3;4 2]/4;
A
svd(A)
[U,S,V] = svd(A)
A - U*S*V'
A=rand(4,2);
[U,S,V] = svd(A)
U'*U
[U,S,V] = svd(A,0)
cd yalefaces/
size(A)
X=imread('subject01.wink','gif');
X=double(X);
size(X)
prod(ans)
image(X)
colormap(flipud(gray(256)))
colormap(gray(256))
shg
image(reshape(A(:,1),243,320))
shg
[U,S,V] = svd(A,0);
size(U)
size(S)
size(V)
semilogy(diag(S))
shg
pcolor(reshape(U(:,1),243,320)),axis ij, shading flat
shg
pcolor(reshape(U(:,2),243,320)),axis ij, shading flat
shg
X=imread('subject01.glasses','gif');
image(X)
shg
x=X(:);
c = U'*x
x=double(X(:));
c = U'*x
plot(c)
shg
pcolor(reshape(U*c,243,320)),axis ij, shading flat
shg
pcolor(reshape(U(:,1:10)*c(1:10),243,320)),axis ij, shading flat
shg
subplot(1,2,1)
pcolor(reshape(U*c,243,320)),axis ij, shading flat
subplot(1,2,2)
pcolor(reshape(U*c,243,320)),axis ij, shading flat
pcolor(reshape(U(:,1:10)*c(1:10),243,320)),axis ij, shading flat
shg
pcolor(reshape(U(:,1:20)*c(1:20),243,320)),axis ij, shading flat
shg