title: np.where and np.select returning error. AttributeError: 'numpy.ndarray' object has no attribute 'select'
body: <p>Trying to use np.select or np.where to run a method on a DataFrame Column.  Either way I do it, I get the error saying the &quot;object has no attribute 'select' (or 'where' if I use np.where).  When I convert the column and check the specific column type, it returns as an numpy.ndarray.  According to the numpy docs, both <a href="https://numpy.org/doc/stable/reference/generated/numpy.where.html" rel="nofollow noreferrer">np.where</a> and <a href="https://numpy.org/doc/stable/reference/generated/numpy.select.html" rel="nofollow noreferrer">np.select</a> should work on numpy arrays.</p>
  <p>Checking type on the Series I converted to a numpy array, after checking the type I try the method and receive the errors:</p>
  <pre><code>type(np.array(daily_std_df['Daily_Std']))
  numpy.ndarray
  
  type(np.array(x))
  numpy.ndarray
  
  ### Apply method to the data frame using np.where OR np.select:
  x = daily_std_df['Daily_Std']
  conditionList = [x &gt; SP_500_std, x &lt; SP_500_std]
  choiceList = ['High', &quot;Not High&quot;]
  daily_std_df[&quot;Risk&quot;] = np.array(x).select(conditionList, choiceList)
  daily_std_df
  ---------------------------------------------------------------------------
  AttributeError                            Traceback (most recent call last)
  &lt;ipython-input-51-42673f1eeafa&gt; in &lt;module&gt;
        3 conditionList = [x &gt; SP_500_std, x &lt; SP_500_std]
        4 choiceList = ['High', &quot;Not High&quot;]
  ----&gt; 5 daily_std_df[&quot;Risk&quot;] = np.array(x).select(conditionList, choiceList)
        6 daily_std_df
  
  AttributeError: 'numpy.ndarray' object has no attribute 'select'
  </code></pre>