文章标题:UFLDL：练习二

矢量化编程实现：如何在matlab里用矢量化编程代替低效率的for循环的，用了MNIST数据集。
首先在train.m文件中把step0里面的各个参数调整成这样：

visibleSize = 28*28;   % number of input units hiddenSize = 196;     % number of hidden unitssparsityParam = 0.1;   % desired average activation of the hidden units.                     % (This was denoted by the Greek alphabet rho, which looks like a lower-case "p",             %  in the lecture notes). lambda = 3e-3;     % weight decay parameter       beta = 3;            % weight of sparsity penalty term

然后把step1里面的写成这样：

images = loadMNISTImages('train-images.idx3-ubyte');patches = images(:,1:10000);% % patches = sampleIMAGES;