title: Apply multiple conditions and apply function to columns
body: <p>I would like to be able to add a new column to a data frame and then use conditions about the values in each row to categorise it into zero, one or multiple categories which would be record in the final column.</p>
  <p>e.g., with this DataFrame, df</p>
  <pre><code>     Name  Height Qualification   Type
  0     Jai     5.1           Msc     []
  1  Princi     6.2            MA     []
  2  Gaurav     5.1           Msc     []
  3    Anuj     5.2           Msc     []
  </code></pre>
  <p>I would like to be able to list multiple category types in the final column based on what is in the rest of the DataFrame.</p>
  <p>e.g.,</p>
  <pre><code>Type A - Height &lt; 6 and Qualification == Msc
  Type B - Height &lt; 5.2
  </code></pre>
  <p>So the result would be</p>
  <pre><code>     Name  Height Qualification   Type
  0     Jai     5.1           Msc     [&quot;A&quot;, &quot;B&quot;]
  1  Princi     6.2            MA     []
  2  Gaurav     5.1           Msc     [&quot;A&quot;, &quot;B&quot;]
  3    Anuj     5.2           Msc     [&quot;A&quot;]
  </code></pre>
  <p>I can use np.select or np.where to do a single category, but can't figure out a nice way to do this with multiple possible categories.</p>