title: Concatenate Numpy ndarray to Pandas dataframe
body: <p>I have a pandas dataframe (d6_y_data_test) which I have just conducted a statistical test on a number of its columns and the results of this test by observation are output in a Numpy NDarray (d8_y_probs). I would like to concatenate the results in the NDarray to the Pandas Dataframe but am having all sorts of trouble:</p>
  
  <p>The first thing I tried is just concatenating them as you would two dataframes:</p>
  
  <pre><code>f2_error_model = pd.concat([d6_y_data_test, d8_y_probs])
  </code></pre>
  
  <p>and I get</p>
  
  <pre><code>TypeError: cannot concatenate a non-NDFrame object
  </code></pre>
  
  <p>So I have tried turning d8_y_probs into a dataframe doing the below for some reason makes each data point into its own column rather than row:</p>
  
  <pre><code>df1 = pd.DataFrame([d8_y_probs])
  </code></pre>
  
  <p>So does anyone know how I can concatenate the Numpy NDArray d8_y_probs to the Pandas DataFrame d6_y_data_test?</p>
  
  <p>Thanks</p>