superimpose density line over hist
This certainly did the trick, Thanks Ted, Sean, Romain, Dimitris, Lian and Andy,
alnlength<-rchisq(1000,4) x<-0.25*(0:100) hist(alnlength,breaks=0.25*(0:100)) lines(x,1000*dchisq(x,4)*0.25)
And apologies for my "newbieness" in the posting,
Albert.