title: How to vertically concatenate two arrays in Python?
body: <p>I want to concatenate two arrays vertically in Python using the NumPy package:</p>
  
  <pre><code>a = array([1,2,3,4])
  b = array([5,6,7,8])
  </code></pre>
  
  <p>I want something like this:</p>
  
  <pre><code>c = array([[1,2,3,4],[5,6,7,8]])
  </code></pre>
  
  <p>How we can do that using the <code>concatenate</code> function? I checked these two functions but the results are the same:</p>
  
  <pre><code>c = concatenate((a,b),axis=0)
  # or
  c = concatenate((a,b),axis=1)
  </code></pre>
  
  <p>We have this in both of these functions: </p>
  
  <pre><code>c = array([1,2,3,4,5,6,7,8])
  </code></pre>