title: Plotting Time series Problem with straight lines between the graph
body: <p>just in plotting there is a straight lines in the graphs. There is no complexity in codes. Maybe something wrong with my data? </p>
  
  <p><a href="https://i.stack.imgur.com/WgV1K.jpg" rel="nofollow noreferrer">my plot with lines</a>
  plotting  y axis= standard deviation data, x axis= date 20XX-20xx 10 year weekly observations. </p>
  
  <pre><code>info3&lt;-c(date,VSP)
  
  Date             VSP
  02/01/2009  44.29181327
  09/01/2009  30.12343114
  16/01/2009  37.34662377
  23/01/2009  45.42791909
  30/01/2009  41.15014822
  ...              ...
  
  Y2=info3[,-1]
  dinfo3&lt;-as.Date(as.character(info3$Date),"%d/%m/%Y")
  plot(dinfo3,Y2$VSP,type="l",col="black",lwd=1)
  </code></pre>
  
  <p>I expect graphs without these lines</p>