[R] problem with ifelse

[Christopher Kelvin]

Dear all,
 The code below is used to generate interval censored data but unfortunately there is an error with the ifelse which i am not able to rectify.
 Can somebody help correct it for me.
Thank you


t<-rexp(20,0.2) 
v<-c(0,m,999) 

y<-function(t,v){
  z<-numeric(length(t ((
    s<-numeric(length(t ((
      for(i in 1:length(t)){
        for(j in 1:length(v-1)) 
        { ifelse ((t[i]>v[j] & t< v[j+1] ),{z[i]<-v[j];s[i]<-v[j+1]},NA)}} 
      return(cbind(z,s))} 

y(t,v)


Chris Kelvin
Institute for Mathematical Research
UPM