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rsurvival-analysissurvival

R survminer::ggsurvplot can't combine due to "atomic vector"?


Reproducible example:

require(Survival)
require(survminer)
require(ggplot2)

set.seed(42)

a <- c(32,291,545, 44,3,792,352, 20,615,169, 61,156, 88,863,255, 33,132,5,
       63,8,964,831, 55,133, 12, 54,261,867, 17, 12,699,233,251,446, 43,223, 
       374, 75, 34, 69,120, 84,134,8,806,8, 48, 86,211, 2436, 61, 81, 87, 12, 
       838, 34, 17,141, 44,155,128,6, 29, 16, 16, 34,130,430,325, 41, 28, 53,
       32,291,545, 44,3,792,352, 20,615,169, 61,156, 88,863,255, 33,132,5,
       63,8,964,831, 55,133, 12, 54,261,867, 17, 12,699,233,251,446, 43,223,
       86, 54,3,630, 93,699, 25,746,6, 46, 22, 60,395,402,151, 26, 38,125, 
       75, 34, 69,120, 84,134,8,806,8, 48, 86,211, 2436, 61,
       191, 49, 59,6, 34, 56,2, 96, 422, 45, 70)

b <- sample(c("Alpha", "Beta", "Gamma"), length(a), replace = T)
c <- sample(0:1, length(a), replace = T)
df <- data.frame(a, b, c)
    
avg <- survfit(Surv(time = a, event = c) ~ 1, data = df)
survminer::ggsurvplot(
  avg,
  conf.int = FALSE,
  censor = FALSE,
  palette = "black",
  linetype = "dashed"      
)  

surv_b <- survfit(Surv(time = a, event = c) ~ b, data = df)
survminer::ggsurvplot(
  surv_b,
  conf.int = FALSE,
  censor = FALSE,
)  

surv_comb <- c(avg, surv_b)

survminer::ggsurvplot_combine(
  surv_comb, 
  data = df,
  combine = TRUE,
  censor = FALSE,
  legend = "right"
)

The two survival curves separately plot without error, but when I try to combine them, I get an error that ! $ operator is invalid for atomic vectors. I have checked just about everything with is.atomic() and I can't find what causes the issue. Could someone help me figure this out, please?


Solution

  • You need to make a list, with your two fits in it, not concatenate the fits.

    fits <- list(avg= avg, surv_b = surv_b)
    
    survminer::ggsurvplot_combine(
      fits, 
      data = df,
      combine = TRUE,
      censor = FALSE,
      legend = "right"
    )