title: How to create new rows in a dataframe based on another row's contents with the same values but in different order?
body: <p>I would like to transform my dataset in a way that for each original row, all the values within it becomes the first one in a new row, while keeping the other values.</p>
  
  <p>I'm not sure this explanation is clear so here is an example:
  let's say I have a data frame that looks like this:</p>
  
  <pre><code>V1          V2            V3       V4          V5         V6
  valve      valves       VALVE      VALVES      Valve     Valves
  vaporizer  vaporizers   Vaporizer  Vaporizers   NA        NA
  </code></pre>
  
  <p>And I would like </p>
  
  <pre><code>V1          V2            V3       V4          V5         V6
  valve      valves       VALVE      VALVES      Valve       Valves
  valves     valve        VALVE      VALVES      Valve       Valves
  VALVE      valves       valve      VALVES      Valve       Valves
  VALVES     valves       VALVE      valve       Valve       Valves
  Valve      valves       VALVE      VALVES      valve       Valves
  Valves     valves       VALVE      VALVES      Valve       valve
  vaporizer  vaporizers   Vaporizer  Vaporizers    NA          NA
  vaporizers vaporizer    Vaporizer  Vaporizers    NA          NA
  Vaporizer  vaporizers   vaporizer  Vaporizers    NA          NA
  Vaporizers vaporizers   Vaporizer  vaporizer     NA          NA
  </code></pre>
  
  <p>This means taking into account the fact that there are NAs (and not to create a new line when there are some).</p>
  
  <p>I've been struggling a lot with this issue since 2 days, thus any help would be greatly appreciated!</p>
  
  <p>Thanks a lot</p>