%MNIST The MNIST database as a PRTools dataset
%
%  [TRAIN,TEST] = MNIST
%   TRAIN_TEST  = MNIST
%
% The MNIST database as supplied by Yann LeCun in PRTools format. It
% contains of 10 classes of handwritten digits of 28 x 28 pixels.
% The trainset has 60000 digits and the testset 1000.
%
% SEE ALSO <a href="http://37steps.com/prtools">PRTools Guide</a>, <a href="http://yann.lecun.com/exdb/mnist/">Original Website</a>
% PRTOOLS, DATASETS, SHOW


function varargout = mnist

varargout = cell(1,nargout);
[varargout{:}] = pr_loadmatfile;

if isempty(varargout{1})
  
  a = pr_getdata(['http://37steps.com/data/prdatafiles/MNIST_train.zip'],42,'mnist_train','',1);
  b = pr_getdata(['http://37steps.com/data/prdatafiles/MNIST_test.zip'],[],'mnist_test','',0);
  % Note that these are datafiles
  user.desc = ['This is the trainset of MNIST.'];
  user.link = ['http://yann.lecun.com/exdb/mnist/'];
  a = setuser(a,user)*datasetm; % convert to dataset
  user.desc = ['This is the testset of MNIST.'];
  user.link = ['http://yann.lecun.com/exdb/mnist/'];
  b = setuser(b,user)*datasetm; % convert to dataset
  a = setname(a,'MNIST');
  b = setname(b,'MNIST');
  
  % save separate and combined files
  [varargout{:}] = pr_savematfile(a,b);
  
end