How to connect dots where there are missing values?

Question

lets take this example:

       test=c(1,5,NA,5,4,1,NA,3,3,5,4,2)

      plot(test,type=\"l\")

This will plot test but will not connect the

Answer 1

Another way that preserves the missing value in the same spots

data=data.frame(x=1:12,y=test)
plot(data)
lines(data)
lines(na.omit(data),col=2)

Or in ggplot2

ggplot(data,aes(x,y))+geom_point()+geom_line(data=na.omit(data))