Cumulative Histogram

cumhist.R

cumhist <- function(x, data=NULL, ...) {
  terms<-as.character(x)
  rhs<-terms[length(terms)]
  splt<-strsplit(rhs,split="|", fixed=T)[[1]]
  var<-splt[1]
  grp<-splt[2]
  lhs<-paste("ecdf(",var,")(",var,")", sep="")
  ff<-paste(lhs, var, sep="~")
  if(!is.na(grp)) {
    ff<-paste(ff,grp,sep="|")
  }
  print(ff)
  xyplot(as.formula(ff),data=data,...)
}

d1 = data.frame(latency=rnorm(1000,300,25), cond=rep("A", 1000))
d2 = data.frame(latency=rnorm(1000,200,10), cond=rep("B", 1000))
d = rbind(d1,d2)
p1 = cumhist(~latency,d)
p2 = cumhist(~latency|cond,d)
print(p1, split=c(1,1,1,2), more=TRUE)
print(p2, split=c(1,2,1,2))