title: numpy range created using percentage increment
body: <p>I would like to create a numpy range from <code>start</code> to <code>stop</code> using a (fixed) percentage increment based on the previous number eg start=100 increment=2% to get 100, 102, 104.04, 106.12 etc</p>
  
  <p>Obviously this can be done by iterating over a list or, more elegantly, using a generator: </p>
  
  <pre><code>def pct_incrementer(start, stop, step_pct):
      val = start
      yield val
      while True:
          val += val * step_pct
          if val &gt;= stop:
              break
          yield val
  
   np.array(list(pct_incrementer(100, 200, 0.02)))
   # or (as I've just learned!)
   np.fromiter(pct_incrementer(100, 200, 0.02), float)  
  </code></pre>
  
  <p>Does numpy (or pandas) have a function to do this natively??  (cos I can't find one!).  Is there, perhaps a way of manipulating <code>np.array([100] * 10)</code> to do the same thing?</p>
  
  <p>Thanks!</p>