title: How to delete specific values from numpy ndarray
body: <p>I have a numpy ndarray that looks like:</p>
  
  <pre><code>[[  0   0   0],
  [  0   0   0],
  [  0   0   0],
  [  0   0   0],
  [  0   0   0],
  [  0   0   0],
  [  0   0   0],
  [225 224 228],
  [163 164 174],
  [205 212 229],
  [116 130 153],
  [ 81 101 132],
  [ 34  56  92],
  [  2  16  35],
  [ 33  44  64],
  [ 38  49  71],
  [ 63  75  99],
  [ 76  88 116],
  [ 45  62  95],
  [ 29  50  88],
  [ 18  40  82],
  [  0   0   0],
  [  0   0   0],
  [  0   0   0],
  [  0   0   0],
  [  0   0   0],
  [  0   0   0],
  [  0   0   0]]
  </code></pre>
  
  <p>I want to delete all the zero elements i.e. <code>[0,0,0]</code>. How can I do this?</p>