[R] Plotting Two Lines

[Jim Lemon]

stats787 wrote:
> Hi,
>
> I am trying to plot the following data such that both variable y and z vs x.
> (ie two lines on a single plot). As the x variable is not numeric, how do I
> go about it? Appreciate if any expert could help. 
> I know I use plot() follow by lines() to add another line to the plot. But
> my problem is i was unable to plot y vs x in the first place.
>   
Hi stats787,
I think this is a replay of a previous problem where the sender expected 
the values on the abcissa to be sorted before plotting. You have the 
additional camoflage of a factor as that set of values. One minor 
problem is that the separator is missing between elements 1 and 2 in the 
eighth line. After fixing that, try this (assuming your data frame is 
named "stats787":

plot(as.numeric(stats787$x)[order(stats787$x)],stats787$y,type="l",col="red")                    

lines(as.numeric(stats787$x)[order(stats787$x)],stats787$z,col="green")


Jim