title: unsupported operand type(s) for /: 'str' and 'float'
body: <p>I have a dataframe as mentioned.
  <a href="https://i.stack.imgur.com/5XmjH.png" rel="nofollow noreferrer">Steam Pressure</a></p>
  <p>I want to add a new column after doing simple math.</p>
  <p>First I tried:</p>
  <pre><code>pd.eval(&quot;HRSGHPSteam = df1.HRSGHPStmPressure/1000&quot;, target=df1)
  </code></pre>
  <p>this gives me <code>TypeError: unsupported operand type(s) for /: 'object' and '&lt;class 'int'&gt;'</code></p>
  <p>then I tried</p>
  <pre><code>df1['HRSGHPSteam'] = df1['HRSGHPStmPressure']/1000
  </code></pre>
  <p>this gives me <code>TypeError: unsupported operand type(s) for /: 'str' and 'int'</code></p>
  <p>Can someone please advise how I can rectify this problem?</p>