title: extract ARIMA specificaiton
body: <p>Printing a fitted model object from auto.arima() includes a line such as<br>
  "ARIMA(2,1,0) with drift,"<br>
  which would be a nice item to include in sweave (or other) output illustrating the fitted model. Is it possible to extract that line as a block?  At this point the best I am doing is to extract the appropriate order from the arma component (possibly coupled with verbiage from the names of the coefficients of the fitted model, e.g., "with drift" or "with non-zero mean.")</p>
  
  <pre><code># R 3.0.2 x64 on Windows, forecast 5.3 
  library(forecast)  
  y &lt;- ts(data = c(-4.389, -3.891, -4.435, -5.403, -2.501, -1.858, -4.735, -1.085, -2.701, -3.908, -2.520, -2.009, -6.961, -2.891, -0.6791, -1.459, -3.210, -2.178, -1.972, -1.207, -1.376, -1.355, -1.950, -2.862, -3.475, -1.027, -2.673, -3.116, -1.290, -1.510, -1.736, -2.565, -1.932, -0.8247, -2.067, -2.148, -1.236, -2.207, -1.120, -0.6152), start = 1971, end = 2010)  
  fm &lt;- auto.arima(y)  
  fm  
  
  # what I want is the line: "ARIMA(2,1,0) with drift`"  
  
  str(fm)  
  paste("ARIMA(", fm$arma[1], ",", fm$arma[length(fm$arma)-1], ",", fm$arma[2], ") with ",intersect("drift", names(fm$coef)), sep = "")
  </code></pre>