title: Iterator to iterate over Excel file
body: <p>I have some data stored in Excel tables(<code>.xlsx</code>), which my current Python script reads them into the memory and uses them for calculations. I will explain my script more with an example.</p>
  
  <p>Say my excel file has this data under a specific column: <code>a = [1,2,3,4,5]</code>.</p>
  
  <p>I am reading this whole thing into the memory using pandas (<code>pd.read_excel()</code>) and running my own iterator function to get:</p>
  
  <pre><code>a0 = [1,2,3,4,5]
  a1 = [5,1,2,3,4]
  a2 = [4,5,1,2,3]
  </code></pre>
  
  <p>and so on. Basically I am shifting every element by some integer amount. <code>a0, a1</code> and <code>a2</code> here appear as lists but they are iterator objects, I don't store them.</p>
  
  <p>As you notice here, <code>a0</code> is always the same as <code>a</code>, and I don't really need to store <code>a</code> in memory because I only need it once, which is what <code>a0</code> does. So what I am trying to do is having some sort of iterator object to iterate over the excel file directly to capture <code>a0, a1</code> and <code>a2</code> as if I were importing <code>a</code> first and then iterating for <code>a0, a1, a2</code> over <code>a</code>.</p>
  
  <p>The reason I am trying to do such a thing is because, the time my script takes for calculations are shorter than what it takes to import the data from Excel. So in order to increase my script in performance, I need to find a way to iterate over Excel rather than saving data into the memory. I would appreciate any help with this.</p>
  
  <p>Addition, my comment: If <code>pandas</code> or some other library had <code>readThisCell()</code> kind of functionality, it would make things easy for me to make my own excel iterator. But I don't know what my options are with pandas or any other library.</p>