[Rd] Wrong behavior of lines.survfit for conf.int="only" (PR#13171)

[diggsb at ohsu.edu]

Full_Name: Brian Diggs
Version: 2.7.2 (2008-08-25)
OS: mingw32 (Windows XP Professional)
Submission from: (NULL) (137.53.146.55)


Description of problem:
The documentation of lines.survfit states that if it is called with
conf.int="only" that the confidence intervals of the survival curve will be
drawn but that the survival curve itself will not. Actual behavior is that both
the confidence intervals and the survival curve are drawn, the same as if
conf.int=TRUE.

Steps to reproduce the problem:
library(survival)
data(cancer)
km <- survfit(Surv(time,status), data=cancer)
plot(km, col=0) #lines drawn in background color, needed to set up the axes
lines(km,conf.int="only") #should draw only the confidence intervals, does draw
both

R version:
platform       i386-pc-mingw32             
arch           i386                        
os             mingw32                     
system         i386, mingw32               
status                                     
major          2                           
minor          7.2                         
year           2008                        
month          08                          
day            25                          
svn rev        46428                       
language       R                           
version.string R version 2.7.2 (2008-08-25)

survival package version:
Version:       2.34-1
Date:          2008-03-31
Packaged:      Wed Apr 2 09:02:54 2008; hornik
Built:         R 2.7.2; i386-pc-mingw32; 2008-08-25 14:57:42; windows

system:
Microsoft Windows XP
Professional
Version 2002
Service Pack 3