title: extract values from time series forecast
body: <p>I have an object <code>forecast</code>. When I execute:</p>
  
  <pre><code>class(forecast)
  </code></pre>
  
  <p>I get:</p>
  
  <pre><code>[1] "mts"    "ts"     "matrix"
  </code></pre>
  
  <p>Does this mean that this is a list of 3 objects of which the last one is a matrix?</p>
  
  <p>When I do:</p>
  
  <pre><code>str(forecast)
  </code></pre>
  
  <p>I get:</p>
  
  <pre><code> Time-Series [1:5, 1:3] from 8153 to 8157: 52 52 52 51 51 ...
   - attr(*, "dimnames")=List of 2
    ..$ : NULL
    ..$ : chr [1:3] "fit" "upr" "lwr"
  </code></pre>
  
  <p>When I do:</p>
  
  <pre><code>head(forecast)
  </code></pre>
  
  <p>I get:</p>
  
  <pre><code>          fit      upr      lwr
  [1,] 51.77675 57.21211 46.34138
  [2,] 51.67965 57.22266 46.13664
  [3,] 51.58255 57.36042 45.80468
  [4,] 51.48545 57.65884 45.31206
  [5,] 51.38835 58.13347 44.6432
  </code></pre>
  
  <p>How do I get the separate values of the first row as indicated by this pseudo code please:</p>
  
  <pre><code>          fit      upr      lwr
  [1,] 51.77675 57.21211 46.34138
  
  fit &lt;- ?
  upr &lt;- ?
  lwr &lt;- ?
  </code></pre>