Exercise:Convolution and Pooling
From Ufldl
(→Step 3a: Convolution) |
(→Step 3a: Convolution) |
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- | If the original layout of < | + | If the original layout of <tt>W</tt> was correct, after flipping, it would be incorrect. For the layout to be correct after flipping, you will have to flip <tt>W</tt> before passing it into <tt>conv2</tt>, so that after MATLAB flips <tt>W</tt> in <tt>conv2</tt>, the layout will be correct. For <tt>conv2</tt>, this means reversing the rows and columns, which can be done with <tt>flipud</tt> and <tt>fliplr</tt>, as we did in the example code above. This is also true for the general convolution function <tt>convn</tt>, in which case MATLAB reverses every dimension. In general, you can flip the matrix <tt>W</tt> using the following code snippet, which works for <tt>W</tt> of any dimension |
<syntaxhighlight lang="matlab"> | <syntaxhighlight lang="matlab"> |