title: Numpy Zeros and String Data Type
body: <p>I have an 18x18 grid of Numpy Zeros and I have 1's and 2's randomly filling the board using the code below.</p>
  
  <pre><code>import numpy as np
  a=np.zeros(324)
  p=np.random.permutation(324)
  a[p[:30]]=1
  a[p[30:60]]=2
  a.reshape(18,18)
  </code></pre>
  
  <p>And it returns the correct numpy array. However, I want to add a random X in there so I changed the first line of the code above to look like</p>
  
  <pre><code>a=np.zeros(324,dtype=str)
  </code></pre>
  
  <p>However, when I run the code, all of the zeros in the array disappears. It just shows up as '_'(without the underscore). Any thoughts to be able to have strings in the array but also have zeros?</p>
  
  <p>Or a better way to create an 18x18 grid that can have strings in it?</p>