title: "plot.new has not been called yet" error in rmarkdown (Rstudio 1.0.44)
body: <p>I am using a recent version of Rstudio with an iMac</p>
  
  <blockquote>
    <p>Version 1.0.44 – © 2009-2016 RStudio, Inc. Mozilla/5.0 (Macintosh;
    Intel Mac OS X 10_12_1) AppleWebKit/602.2.14 (KHTML, like Gecko)</p>
  </blockquote>
  
  <p>And I noticed the notebook function for rmarkdown files. When generating plots, the usual "Plots window" is not used any more, and the plots are generated just below the code chunk.</p>
  
  <p>And I have an error for the following code: </p>
  
  <pre><code>plot(seq(1,10,1))
  abline(a=0,b=1)
  </code></pre>
  
  <p>The error is showed below the code chunk : </p>
  
  <pre><code>Error in int_abline(a = a, b = b, h = h, v = v, untf = untf, ...) : plot.new has not been called yet
  </code></pre>
  
  <p>However, when knitting the whole rmarkdown file, there is no error.</p>
  
  <p>So I would like to know how to avoid the error:</p>
  
  <ul>
  <li>by using another code</li>
  <li>by using the "Plots window"</li>
  <li>or another way.</li>
  </ul>