title: How to declare and fill an array in NumPy?
body: <p>I need to create an empty array in Python and fill it in a loop method. </p>
  
  <p><code>data1 = np.array([ra,dec,[]])</code></p>
  
  <p>Here is what I have. The ra and dec portions are from another array I've imported. What I am having trouble with is filling the other columns. 
  Example. Lets say to fill the 3rd column I do this:</p>
  
  <pre><code>for i in range (0,56):
      data1[i,3] = 32
  </code></pre>
  
  <p>The error I am getting is: </p>
  
  <blockquote>
    <p>IndexError: invalid index for the second line in the aforementioned
    code sample.</p>
  </blockquote>
  
  <p>Additionally, when I check the shape of the array I created, it will come out at <code>(3,)</code>. The data that I have already entered into this is intended to be two columns with 56 rows of data. </p>
  
  <p>So where am I messing up here? Should I transpose the array? </p>