[R] line plot through NA

[Peter Dalgaard]

rggefrm at ucl.ac.uk writes:

> Dear R-help list,
> 
> I hope I did not miss something obvious, because my question seems very 
> simple, but I couln't figure out how to do it.
> 
> If I have the following data:
> Day<-c(1,2,3,4,5,6,7)
> V<-c(5,NA,10,30,45,NA,10)
> than the line in plot
> 
> plot(V~Day, type="b")
> 
> will start with the 3rd value and stop stop at the 5th value because all NA 
> are omitted. Is there now a parameter which can be added to the plot 
> function so the line will start with with the first value and skip the NA 
> values and can this than applied to xyplots.

AFAIK, this is not controlable via options or graphics parameters. So
the way forward would be to remove the points with missing data.
Here's one way:

plot(V~Day, type="b", data=na.omit(data.frame(V,Day)))

and another:

plot(V~Day, type="b", subset=complete.cases(V,Day))

and another (messes up axis labels, though)

s <- complete.cases(V,Day)
plot(Day[s], V[s], type="b")



-- 
   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
  c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
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