title: Appending Pandas dataframes row-wise
body: <p>I have checked <a href="https://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.append.html" rel="nofollow noreferrer">append</a> and it should be doing the job, but for some reason I cannot figure out the row-wise append isn't working.</p>
  
  <p>I have two dataframes with size (x,y). I want to combine these two row-wise, so the final dataframe is of size (2x,y). </p>
  
  <p>I have tried to do the following:</p>
  
  <pre><code>frame_combined = frame_1.append(frame_2, ignore_header=True)
  frame_combined = pd.concat([frame_1, frame_2], axis=1) # also axis=0
  </code></pre>
  
  <p>Edit: Doing these gives me a (2x,2y) dataframe. And also my dataframe has no header.</p>
  
  <p>What am I missing that I get a dataframe that is appended both row and column-wise? And how can I do a simple row-wise append?</p>
  
  <p>Thank you.</p>