dat = textread('digitsTrain.dat');
X = dat(:,1:end-1);
y = dat(:,end);

%Scale the image features to be floating point numbers from 0 to 1
X = double(X)./255;

%Look at some digits
[m,n] = size(X);

imy = sqrt(n);
imx = imy;

%Find all 1's
i1 = find(y == 1);
%Grab the first one
i1 = i1(1);
im1 = reshape(X(i1,:),[imy imx])';

%Find all 2's
i2 = find(y == 2);
%Grab the first one
i2 = i2(1);
im2 = reshape(X(i2,:),[imy imx])';

%Find all 3's
i3 = find(y == 3);
%Grab the first one
i3 = i3(1);
im3 = reshape(X(i3,:),[imy imx])';

subplot(311); imagesc(im1); axis square;
subplot(312); imagesc(im2); axis square;
subplot(313); imagesc(im3); axis square;
colormap gray;