r - How to assign colors to groups in survival graphs -

i have full control on colors used display group graphs using ggsurv. you'll find below toy example reproduce i've seen (mostly taken there):

require(data.table)  # function create synthetic survival data simulweib <- function(n, lambda, rho, beta, ratec) {   # covariate --> n bernoulli trials   x <- sample(x=c(0, 1), size=n, replace=true, prob=c(0.5, 0.5))    # weibull latent event times   v <- runif(n=n)   tlat <- (- log(v) / (lambda * exp(x * beta)))^(1 / rho)    # censoring times   c <- rexp(n=n, rate=ratec)    # follow-up times , event indicators   time <- pmin(tlat, c)   status <- as.numeric(tlat <= c)    # data set   data.frame(id=1:n,              time=time,              status=status,              x=x) }  set.seed(1234) nbgroups <- 7 dat <- list() for(k in 1:nbgroups) {   dat.onegp <- simulweib(n=10, lambda=0.01, rho=1, beta=-0.6, ratec=0.001)   # fit <- coxph(surv(time, status) ~ x, data=dat.onegp)   dat.onegp <- mutate(dat.onegp, group = paste0("g",k))   dat[[k]] <- dat.onegp }  dat.df <- rbindlist(dat) dat.df.survcurv <- survfit( surv(dat.df$time, dat.df$status) ~ dat.df$group ) # vector colors used cols = colorramppalette(brewer.pal(9, "set1"))(nbgroups)  ggsurv(dat.df.survcurv, size.est = 1 ) +   guides(linetype = false) +   scale_colour_manual(name = "exp. groups",  breaks = sort(dat.df$group), values = cols) 

running twice give 2 different sets of color-group assignment, , don't want that. need groups displayed same color, consistency other graphs in report.

nb: have found out order in colors displayed linked survival data, can't figure out how force color assignment.

any appreciated!

found in this post ! solution use limits instead of breaks

ggsurv(dat.df.survcurv, size.est = 1 ) +   guides(linetype = false) +   scale_colour_manual(name = "exp. groups",  limits = sort(dat.df$group), values = cols)