title: forecasting multiples products data
body: <p>I would like to predict the next 5 orders and the quantity of the 3 products in each order. </p>
  
  <p>I am a beginner using <code>r</code> and <code>timeseries</code> and I saw examples using <code>arima</code> but they're applied only to measure one thing and not multiple products like in my example. </p>
  
  <p>Should I use arima? 
  What should I do exactly?</p>
  
  <p>Sorry for my bad English. Thank you in advance.</p>
  
  <pre><code>dateordrer,product1,product2,product3
  12/01/2012,2565,3254,635
  25/01/2012,2270,3254,670
  01/03/2012,2000,785,0
  05/05/2012,300,3254,750
  26/06/2012,3340,0,540
  30/06/2012,0,3254,0
  21/06/2012,3360,3356,830
  01/07/2012,2470,3456,884
  03/07/2012,3680,3554,944
  05/07/2012,2817,3854,0
  09/07/2012,4210,4254,32
  09/08/2012,0,3254,1108
  13/09/2012,4560,5210,952
  25/09/2012,4452,4256,1143
  31/09/2012,5090,5469,199
  25/11/2012,5100,5569,0
  10/12/2012,5440,5789,1323
  11/12/2012,5528,5426,1350
  </code></pre>