title: What does bit fail mean?
body: <p>My neural network has 22 inputs of 5184 values (two digit values, images converted to bytes), and I tried to set 2 output neurons with value <code>0</code> or <code>1</code>, like:</p>
  
  <pre><code>&lt;input data line with 5184 values&gt;
  0 1
  &lt;input data line with 5184 values&gt;
  1 0
  &lt;input data line with 5184 values&gt;
  .
  .
  .
  </code></pre>
  
  <p>From training results :</p>
  
  <pre><code>Epochs            1. Current error: 0.3750000000. Bit fail 33.
  </code></pre>
  
  <p>What is this bit fail? <a href="http://leenissen.dk/fann/html/files/fann_train-h.html#fann_get_bit_fail" rel="nofollow noreferrer">The documentation says</a>:</p>
  
  <blockquote>
    <p>The number of fail bits; means the number of output neurons which
    differ more than the bit fail limit.</p>
  </blockquote>
  
  <p>How can I have 33 output neurons fail for only 2 output neurons? I imagine this 33 could be from a total of 44 outputs (2 from each of the 22 inputs). But documentation does not confirm this.</p>