title: How to set the "lwd" parameter in plot.xts?
body: <p>I just want to set the line width of the line I'm plotting to be of a certain value. The rest (gridlines, border around graph) should remain 1.0 of width.</p>
  
  <p>But if I set <code>par(lwd=2)</code> all lines are wider. If I set <code>plot.xts(AAPL,lwd=2)</code>, I get an error:</p>
  
  <pre><code>Error in axis(1, at = xycoords$x[ep], labels = names(ep), las = 1, lwd = 1,  : 
    formal argument "lwd" matched by multiple actual arguments
  </code></pre>
  
  <p>Heres my code:</p>
  
  <pre><code>library(quantmod)
  getSymbols("AAPL")
  par(lwd=2)
  plot.xts(AAPL)
  </code></pre>