title: Pandas: Iterate through columns and starting at one column
body: <p>Does anyone know how to incorporate a forloop for columns but start at any column? (The third one for this scenario)</p>
  
  <p>Lets say this is the dataframe:</p>
  
  <pre><code>spice smice skice bike dike mike 
  1     23     35    34   34   56 
  135   34     23    21   56   34
  231   12     67    21   62   75
  </code></pre>
  
  <p>I want to iterate through <strong>skice, bike, dike, and mike <em>only</em></strong></p>