Dear R-help list, I have a problem with the tick marks of a Kaplan-Meier survival plot. Here is a sample: follow.up<-c(10,20,30,40,50,60,70,80,90,100) #months dead<-c(1,1,1,0,1,1,0,0,0,0) KM <-survfit(Surv(follow.up, dead)) plot(KM) The result is a nice plot. However, our research group thinks it may be a better idea to place the ticks to the years on the time scale, i.e. 0, 12, 24, 36 etc. months. Is this possible with R? I tried to look it up and the most relevant manual page was ?axis, option at - but I could not make this work together with the plot command. plot(KM, axis=axis(1, at=c(0,12,24,36))) #this does not what I wanted Any ideas? Thank you, Gabor
On Mon, 2003-10-06 at 10:55, Gabor Borgulya wrote:> Dear R-help list, > > I have a problem with the tick marks of a Kaplan-Meier survival plot. > Here is a sample: > > follow.up<-c(10,20,30,40,50,60,70,80,90,100) #months > dead<-c(1,1,1,0,1,1,0,0,0,0) > KM <-survfit(Surv(follow.up, dead)) > plot(KM) > > The result is a nice plot. However, our research group thinks it may be > a better idea to place the ticks to the years on the time scale, i.e. 0, > 12, 24, 36 etc. months. Is this possible with R? > > I tried to look it up and the most relevant manual page was ?axis, > option at - but I could not make this work together with the plot > command. > > plot(KM, axis=axis(1, at=c(0,12,24,36))) #this does not what I wanted > > Any ideas? > > > Thank you, > > GaborTry the following: # Plot without the x axis being labeled plot(KM, xaxt = "n") # Now draw the x axis labels and tick marks axis(1, at = c(0, 12, 24, 36, 48, 60, 72, 84, 96)) HTH, Marc Schwartz
Gabor Borgulya wrote:> Dear R-help list, > > I have a problem with the tick marks of a Kaplan-Meier survival plot. > Here is a sample: > > follow.up<-c(10,20,30,40,50,60,70,80,90,100) #months > dead<-c(1,1,1,0,1,1,0,0,0,0) > KM <-survfit(Surv(follow.up, dead)) > plot(KM) > > The result is a nice plot. However, our research group thinks it may be > a better idea to place the ticks to the years on the time scale, i.e. 0, > 12, 24, 36 etc. months. Is this possible with R? > > I tried to look it up and the most relevant manual page was ?axis, > option at - but I could not make this work together with the plot > command. > > plot(KM, axis=axis(1, at=c(0,12,24,36))) #this does not what I wantedAlmost. See ?axis: plot(KM, xaxt="n") axis(1, at = seq(0, 100, 12)) Uwe Ligges> Any ideas?> > Thank you, > > Gabor > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help
Hopefully, someone who knows will answer. In case that won't happen,
I'll tell you what I would do that would likely produce the desired
result fairly quickly -- but longer than it would take me to test it:
1. class(KM) = "survfit".
2. methods(plot) includes "plot.survfit".
3. ?plot.survfit reveals options I don't fully understand. I'd work
the examples and experiment to see if I could do what I wanted easily
with the existing function.
4. If that didn't work, I'd list "plot.survfit", copy it to a
file,
find the "plot" command, and add "axes=FALSE" to the
argument list. I'd
follow that with "axis(1, ...)" to add the x-axis I want and
"axis(2)"
to add the default y axis.
This general approach has worked in other contexts, so I believe
something like this would likely work here.
hope this helps. spencer graves
Gabor Borgulya wrote:
>Dear R-help list,
>
>I have a problem with the tick marks of a Kaplan-Meier survival plot.
>Here is a sample:
>
>follow.up<-c(10,20,30,40,50,60,70,80,90,100) #months
>dead<-c(1,1,1,0,1,1,0,0,0,0)
>KM <-survfit(Surv(follow.up, dead))
>plot(KM)
>
>The result is a nice plot. However, our research group thinks it may be
>a better idea to place the ticks to the years on the time scale, i.e. 0,
>12, 24, 36 etc. months. Is this possible with R?
>
>I tried to look it up and the most relevant manual page was ?axis,
>option at - but I could not make this work together with the plot
>command.
>
>plot(KM, axis=axis(1, at=c(0,12,24,36))) #this does not what I wanted
>
>Any ideas?
>
>
>Thank you,
>
>Gabor
>
>______________________________________________
>R-help at stat.math.ethz.ch mailing list
>https://www.stat.math.ethz.ch/mailman/listinfo/r-help
>
>