title: Can someone explain implicit "for loops" to me?
body: <p>I am very sorry, I do not understand implicit for loops. So I thought I could ask whether someone will explain this a bit more for me. </p>
  
  <p>I have - under great pains - written the following implicit for loop:</p>
  
  <pre><code>ueberdata= [1,5,2,6,1,2,3,4,1,3,5,6]
  order = [1,3,5]
  ind = [list(ueberdata).index(i) for i in order]
  </code></pre>
  
  <p>this gives me the indices of the first occurrences of the stuff in order. </p>
  
  <pre><code>ind : 0,6,11
  </code></pre>
  
  <p>So far so fine. Now I want to expand this example. Maybe ueberdata is bigger. Maybe I would now like to have ALL the indices. And I am stumped. I have to nest these for loops somehow. Can someone help me understand this good enough to solve this problem?</p>
  
  <p>Some clarification (sorry guys, i really need to express myself better):
  What i essentially want to do is plot a dataset. I have these 3 types of datapoints i want to see on my plot. Now my dataset is of course longer than 3 :). And I want to plot another column, so I need those indices. Sorry for telling that just now, but I thought it might distract from my question. I want to plot all datapoints in my file, not just the first set. </p>