title: ggplot2 geom_line() to skip NA values
body: <p>I have a data set that has multiple NA values in it.  When plotting this data, ggplot's geom_line() option joins lines across the NA values.  Is there any way to have ggplot skip joining the lines across NA values?</p>
  
  <p><strong>Edit:</strong> A thousand apologies to all involved.  I made a mistake in my manipulation of the data frame.  I figured out my problem.  My x axis was not continuous when I created a subset.  The missing data had not been replaced by NAs, so the data was being linked because there were no NAs created in the subset between rows.</p>