problems with loop and plot function

Hi all R users,

I have problems with my second loop for drawing the three curves in
the same graphic. I need help please

Thank you in advance

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simulation <- function(k, n){

conc <- seq(0,100,by=0.5)
#choixg <- seq(1, length(conc))
choixg <- rep(0,length(conc))
for (i in 1:length(conc)){
    choixg[i] <- (k + conc[i])^n/((k+conc[i])^n + (k+1)^n)

    }
   #return(data.frame(choixg, conc))
   return(list(choixg=choixg, conc = conc))
}
#cbind(simResult$conc, simResult$choixg,
#format(Sys.time(),"%H:%M:%S"))

for( n in c(1,3,5)) {
 x <- NULL; y <- NULL
 simResult <- simulation (5,n)
 conc <- simResult$conc
 choixg <- simResult$choixg
 prin("n");  print(c(k=5, n))
 points(conc, log10(1-choixg), main ="fonction de choix", col= n,
 pch=20,
lwd = 3,
xlab = " concentration", ylab="proba de choisir la gauche", type="l")
}


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Lassana KOITA
Etude S??curit?? et Exploitation a??roportuaires / Aerodrome Safety &
Statistical analysis Service Technique de l'Aviation Civile (STAC) /
Civil Aviation Technical Department Direction G??n??rale de l'Aviation
Civile (DGAC) / French Civil Aviation Tel: 01 49 56 80 60 Fax: 01 49
56 82 14 E-mail: Lassana.Koita at aviation-civile.gouv.fr