R：生存包改变x轴范围内的KM曲线图

Question

我正在使用生存包为两个群体生成KM曲线，但是当我尝试定义xmax参数时，我无法将x轴范围从0-15扩展到0-50.

这是我的代码：

 library(sm)
library(survival)
comb = read.csv("S:/Novocure/ChemoSKTime2Resp.csv", head = TRUE)
comb
survobj = with(comb, Surv(SK.response.time,Censored))
survobj

# Compare the survival distributions of nonresponders(0) and responders(1)

fitresp = survfit(survobj ~ response, data=comb)
fitresp
summary(fitresp)

# plot the survival distributions by response

plot(fitresp, xlab="Tumor Progression Time in Months", 
  ylab="% Progressed", yscale=100, col=c("red","blue"),
  main="Chemo Time to Tumor Progression Distribution", xmax = 50) 
  legend("topright", title="Chi-sq = 5.2, P = 0.0222", 
  c("Non-responders", "Responders"), fill=c("red", "blue"))

Answer 1

xmax的{​​{1}}参数似乎只缩短了x轴的范围。要扩展它，请改为使用参数plot.survfit：

xlim