title: Create empty matrix Python
body: <p>I simply want to create an empty 10*3*2 array with Python.</p>
  
  <p>I first thought of these one, but this is not working:</p>
  
  <pre><code>parameters = [ [ [] * 2 ]*3 ] * 10
  </code></pre>
  
  <p>this gives me a vector of ten vectors, with three [] elements in it:</p>
  
  <pre><code>[[[], [], []], [[], [], []], [[], [], []], [[], [], []], [[], [], []], 
  [[], [], []], [[], [], []], [[], [], []], [[], [], []], [[], [], []]]
  </code></pre>
  
  <p>that is , if I want to access parameters[0][0][1] I am out of bounds, whereas I want a dimension 2 for the innermost vectors along the third dimension.</p>
  
  <p>then I thought of this</p>
  
  <pre><code>[ [ [[] * 2] ]*3 ] * 10
  </code></pre>
  
  <p>I was thinking that <code>[[] * 2]</code> would now bring me the thing I want, an innermost two elements vector. I obtain </p>
  
  <pre><code>[[[[]], [[]], [[]]], [[[]], [[]], [[]]], [[[]], [[]], [[]]], 
  [[[]], [[]], [[]]], [[[]], [[]], [[]]], [[[]], [[]], [[]]], 
  [[[]], [[]], [[]]], [[[]], [[]], [[]]], [[[]], [[]], [[]]], [[[]], [[]], [[]]]]
  </code></pre>
  
  <p>So, how to do it, or how to escape this initialization?</p>
  
  <p>Kd rgds.</p>